ID

A Selected Night Blooming Cereus

This very fine specimen is the result of careful selection

by Mr. Burbank, from large numbers of seedlings. The flowers

of this variety are nearly nine inches in diameter. They open early

in the morning and are completely withered by ten or eleven

o'clock. It will be noted that two of the blossoms on the

right hand stalk have withered and that they are

marked with strings to indicate that their seed

is to be saved for future experiments.

LUTHER BURBANK

HIS METHODS AND DISCOVERIES AND
THEIR PRACTICAL APPLICATION

PREPARED FROM
fflS ORIGINAL FIELD NOTES

COVERING MORE THAN 100,000 EXPERIMENTS

MADE DURING FORTY YEARS DEVOTED

TO PLANT IMPROVEMENT

WITH THE ASSISTANCE OF

The Luther Burbank Society

AND ITS
ENTIRE MEMBERSHIP

UNDER THE EDITORIAL DIRECTION OF

John Whitson and Robert John

AND

Henry Smith Williams, M. D.9 LL. D,

VOLUME X

ILLUSTRATED WITH

105 DIRECT COLOR PHOTOGRAPH PRINTS PRODUCED BY A

NEW PROCESS DEVISED AND PERFECTED FOR

USE IN THESE VOLUMES

NEW YORK AND LONDON

LUTHER BURBANK PRESS

MCMXV

Copyright. 1915, by

The Luther Burbank Society

Entered at Stationers' Hall, London
All right* reserred

Volume X— By Chapters

Foreword Page 3

Getting the Utmost Variation
Out of a Flower

—How the Chinese Balloon Flower

Was Trebled.

7

II Improvements in the Much
Improved Iris

—And a Few Other Old os\

Favorite. i>9

TTI The Tigridia and Some
Interesting Hybrids

—New Charms in Far-away _ _

Flowers.

IV Four Common Dooryard Flowers —
And Their Improvement

— Work on the Verbena, the Pink, the Petunia

and the Geranium

107

V The Everlasting Flower, and Some
Common Exotics

— The Australian Star Flower and Plants IOC

From Orient and Tropics lot)

VI The Hybrid Larkspur— and
Other Transformations

— Introducing a Miscellaneous i /TT

Company 10 /

VII Ornamental Palms and
Climbing Vines

— Views on Artistic -. xv^

Treatment .................................. ......... 1""

VIH Lawns and Their
Beautincation

—Some Old and New Shrubs
and Grasses

IX Field and Flower
Garden

—Some Practical Hints for
Their Betterment

List of Direct Color Photograph Prints .......... 305

The Balloon Flower

The upper specimen shows the form of the flower just be-
fore opening, from which the name is derived. It will be seen
that the balloon-shape entirely disappears when the blossom has
opened, as in the lower figure. This specimen shows the
single row of petals characterizing the variety with
which Mr. Burbank's experiments began.

GETTING THE UTMOST VARIATION
OUT OF A FLOWER

How THE CHINESE BALLOON-FLOWER
WAS TREBLED

IN illustrating the possibilities of flower devel-
opment, the case of the Chinese balloon-flower
(Platijcodon) will answer as well as another.

I had been for some time working with a bed
of these flowers, with an eye to the increase of
their beauty of form, their size, clearness and
intensity of color, and the closer and more grace-
ful placing of blossoms on the stalk. As to all of
these matters, the existing balloon-flowers left a
good deal to be desired.

My method of work was that which I have
already outlined so fully in connection with other
flowers. The essentials of it, as the reader is
aware, are first the careful scrutiny of the entire
colony to discover the individual that is the very
best of all as to the particular character in ques-
tion. This individual is selected and its seed
carefully preserved.

[VOLUME X-— CHAPTER I]

LUTHER BURBANK

If the three or four different qualities, improve-
ment of which is desired, are not combined to best
advantage in any single individual, then it is neces-
sary to select an individual for each quality, and
to carry forward three or four lines of experiment
at the same time.

It will be recalled that in developing a special
variety of small sweet canning pea, with the qual-
ities of uniform ripening, of small seed, and of
seeds of uniform number and equal size in the
pod, I was enabled to find these qualities exhibited
in such combination that the experiment went for-
ward rapidly, so that in the course of six genera-
tions I had developed precisely the variety of pea
that was desired.

But it will also be recalled that half a dozen
other lines of experiment were carried forward
at the same time, using the same group of peas,
that led finally to the production of as many quite
different varieties, characterized by large size of
seed, by lentil-shaped seeds, and the like. And
these secondary experiments were carried out
without in any way interfering with the primary
one. It was merely that, in searching among the
different vines, I could not fail to notice individ-
ual plants that showed interesting characteristics,
and nothing more was required than to mark these
differently from the others and save their se^ed.

[8]

I

Double Balloon Flower

This picture, like the preceding one, shows both the bal-

loon-shaped buds and the open flower. But this is a developed

variety, in which the petals have been increased in number tnrougn

the methods of selective breeding described in the text.

LUTHER BURBANK

So in such a case as that of the balloon-flower,
where it is desired to increase three or four quite
different qualities — in this case size, beauty of
form, manner of placement of blossoms, and in-
tensity and clearness of color — it does not so very
greatly matter whether in the early generations
one finds the different qualities combined in a
single individual, or whether, as is more likely,
he finds one individual that is most graceful,
another that has blossoms placed on the stalk in
the best manner, and a third that shows to best
advantage as to intensity and clearness of color.

It is much more probable, in practice, that the
second alternative will be the one actually pre-
sented. Indeed, it is altogether unlikely, when new
qualities, such as these, that have not hitherto at-
tracted the attention of the cultivator of the plant,
are in question, that one will find a single individ-
ual that surpasses all its fellows as to each quality.

In point of fact, with the balloon-flowers, it
was necessary to save seed of three or four indi-
viduals and search among their progeny in turn
in the following season, and make additional
selections that involved a number of individuals.

But when selection has been carried to a stage
where we have one race of balloon-flowers pre-
senting plants that are uniformly of graceful and
attractive form, and another race that has the

[10]

ON EXTREME VARIATION

flowers arranged in a satisfactory way on the stalk,
and a third race that produces flowers of a brilliant
white color, the materials are in hand for an
amplification of the experiment along lines with
which the reader is already familiar, through
which the desired combination of these traits in a
single race may be effected with almost absolute
certainty.

THE COMBINATION OF QUALITIES

The method in question consists, of course, in
cross-pollenizing the best individuals of the three
new races. Of course, one cannot blend three
strains in a single cross-pollenizing experiment.
But one can cross-pollenize specimens of each one
of the three with each of the others, making the
cross reciprocal in all cases to make quite sure.
Each of the new hybrid races will thus blend, in
one way or another, the traits of two of the parent
forms.

Selection being made to find the best types
among these two crossbred races, the ones selected
will, of course, be inter-pollenized and their off-
spring, representing the second generation from
the three parent forms, will combine all the hered-
itary factors of their three specialized ancestors.

Among these second generation hybrids there
will be found, in all probability — if large numbers
of specimens are examined — some individuals that

ON EXTREME VARIATION

will combine in the superlative degree the quali-
ties of gracefulness of vine of one grandparent
with the satisfactory arrangement of flowers of
the second grandparent and the brilliant white-
ness of blossoms of the third grandparent.

It is then an obvious procedure to save the seed
of this individual, and while we must expect wide
variation among the plants grown from that seed,
there will almost certainly be some among them
that will reproduce the combined good qualities
of the parent, and further selection along precisely
the same line — what I sometimes speak of as "line
breeding" — will result in fixing of the type, so
that we shall have the variety, hitherto existing
only in our imagination, which we have all along
been seeking to produce.

Moreover, not alone shall we have produced a
type which combines all the best qualities of the
different members of the original balloon-flowers,
but our new race will almost certainly present
these characters in markedly accentuated form.
The perfected balloon-flower will be more grace-
ful in form than the most graceful one of the orig-
inal colony. It will have its blossoms much more
artistically grouped on the stalk than any balloon-
flower that has hitherto been seen, and the color
of these blossoms will be cleared and more bril-
liant than those of any individual member of the

[13]

LUTHER BURBANK

original colony, whether blue, white, or interme-
diate, as may readily be demonstrated by compar-
ison if the original colony has been preserved, and
is now represented by unselected progeny.

Of course, in my own experiments, the unse-
lected members would usually have been de-
stroyed, but the worker who experiments on a
smaller scale may find it desirable to preserve the
old colony, or some members of it, if for no other
purpose than to find encouragement in making
such a comparison as that just suggested.

The results, as I have said, are sure to be
encouraging if you have carried out the experi-
ment in the way just outlined. Nothing more is
required than the use of your eyes and reasonable
judgment in selecting the best specimens; care in
the preservation of the seeds; cultivation of the
seedlings in the way we have elsewhere fully de-
scribed; and persistency in following up the
experiment.

I have a good many times pointed out that in
such experiments there may not be very much
encouragement in the first generation or two.
Some forms of plant, and in particular those that
have not been very much under cultivation, or
that are represented by only one or two species,
may hold fixedly to their type and show at first
only a slight range of variation. In such cases

[14]

Double, and Tending Toward Tripleness

Here the tendency of the balloon flower to increase its
petals has taken on another phase, in that there is a rudi-
mentary third row of petals, represented by a transformed stamen.
This obviously is promising material for further experiments.

LUTHER BURBANK

you must be content to go forward by very slow
stages, taking but the shortest step ahead with
each generation for the first two or three years.

But even where progress is as slow as this in
the beginning, the time will almost surely come
when the effect of what I have several times
referred to as the momentum of variation begins
to be felt. Some season, to your surprise and
delight, you will discover that the plants are vary-
ing much more widely than they have done
hitherto.

Instead of having to scrutinize your seedlings
with the utmost care to determine which ones are
largest and most vigorous; and then in turn scru-
tinize with equal care the blossoms — when they
appear — to determine which are largest and most
brilliant, you will find that some few seedlings
will jump ahead of the others as if they belonged
to another race, bringing to your mind the famil-
iar tale of Jack's Beanstalk, or the less familiar
story of Darwin's Hero morning-glory, which ap-
peared suddenly after several generations of
selection.

When the seedlings which thus practically
select themselves have come to blooming time,
your delight will be enhanced as you discover
that the blossoms they bear are markedly larger
and more brilliant than any you have seen before.

[16]

ON EXTREME VARIATION

Now all your disappointment and discourage-
ment of the first day is forgotten. Now your en-
thusiasm is reanimated and accentuated. From
this time forward you carry on the experiment
with renewed zeal, and you feel confident at last
that the coveted goal is within sight.

PLANTS THAT TEND TO VARY

Of course there are other plants that give en-
couragement from the very outset. Such is the
case with almost any of the familiar cultivated
plants, of which there are many species and varie-
ties that have long been given attention by the
horticulturist.

Suppose, for example, that you were to plant
all the seeds taken from the seed pods of a single
dahlia. Perhaps you have done this on occasion,
not with any thought of making new experiments
or developing a new variety, but merely in the
hope of reproducing the characteristics of the best
and most beautiful dahlia among the number in
your garden. In that case you have doubtless been
subjected to bitter disappointment. For when the
carefully nurtured seedlings came finally to bloom-
ing time, instead of presenting flowers closely sim-
ilar to those of the parent form, they have shown,
in all probability, the widest range of variation —
not one of them perhaps has been closely similar
to the parent. Nor, perhaps, were any two pre-

[17]

Yet Another Step Toward Tripleness

With this balloon flower several of the stamens have
turned into petals of a rudimentary type. If carefully selected,
the progeny of this flower should, within a generation or two, have
some representatives with three rows of fully formed petals,
in striking contrast with the single-flowered parent-
forms a few generations removed.

ON EXTREME VARIATION

cisely alike. Among them you could discover
resemblances to all the other dahlias in your gar-
den and, indeed, to a large proportion of those
that you had seen pictured in the seed catalogues.

In a word, your dahlia seeds show that they
contain the racial strains of a great variety of an-
cestors, and they present a variation that is truly
disconcerting to the gardener whose sole desire
was to produce a lot of dahlias of uniform char-
acter.

In one case, recorded by Darwin, an experi-
menter listed no fewer than eighteen different
varieties of the dahlia grown in the first genera-
tion from the seed of a single plant, and of course
there were all manner of intermediate forms. In
the listed eighteen only six corresponded pretty
closely to certain named or catalogued varieties.
It would perhaps more truly present the record if
we were to say that there were not eighteen dif-
ferent varieties merely, but as many varieties as
there were individual plants.

But while such an experience as this is utterly
disconcerting to any amateur whose only thought
is to produce a bed of flowers of uniform color or
character, the same experience would offer pre-
cisely the opportunity that the would-be developer
of new varieties is seeking. Now it is not a case
of hunting here and there throughout a company

[19]

LUTHER BURBANK

of seedlings for one that differs by a shade from
the others. It is a case of selecting two or three
or a dozen individual plants that present features
that attract the experimenter; and selecting their
seed to be planted the following year in individual
plots, that the experiment may be carried forward,
generation after generation, just as before so far
as principles are concerned — but very differently
as regards results, inasmuch as now there is the
most striking departure in each successive gen-
eration from the characteristics of the parent form.

How wide the departure may be within a few
generations is well manifested by the dahlias, since
these plants, as we have already learned, have all
been developed in the space of about a century
from wild originals. Moreover, by no means
are many generations represented as might be
supposed, inasmuch as the dahlia is propagated
usually from the bulb, and it is only now and
again that an experimenter has taken the plant in
hand to raise it from the seed and separate out
new varieties.

That a plant which in its wild form is an ordi-
nary sort of composite — not very different from
the Black-Eyed-Susans and allied sunflower-like
plants that abound by every roadside — could be
developed in a comparatively short series of gen-
erations into the extraordianry flower with solid

[20]

Work with the Calendula

Mr. Burbank has a large bed of these flowers in his gar-
den now, and in recent seasons he has been testing it with an
to the range of its possible variations. It is a flower with which
any amateur may work readily and to advantage.

LUTHER BURBANK

heads, and presenting the gorgeous anH variegated
colors of the dahlia of to-day, is in itself an object
lesson in the possibilities of plant development
that is nothing less than inspiring.
UNEXPECTED RESULTS

Not only may plants be led along the line of
some desired variation, but there is an element of
chance in the enterprise that adds very greatly
to its interest.

There is always a certain allurement about the
happening of the unexpected. It is highly gratify-
ing to select a plant for some desired quality and
to have it respond to selection in such wise that a
variety presenting this quality is finally produced.
But it is doubly gratifying to see here and there,
quite unexpectedly, the putting forth of a flower
of an unpredicted color, or the development of a
form of which one hitherto had no conception.

In a field of cultivated poppies, for example,
where there were millions of specimens, all of sub-
stantially identical color, so that the field made a
blazing sheet of yellow, I have come upon a single
blossom of the purest white.

To find this white blossom, isolated among the
millions, is an experience that repays one for
years of earnest effort and makes amends for
almost any antecedent disappointment.

It was such a chance discovery as we have seen

[22]

ON EXTREME VARIATION

that gave the world the wonderful new race of
white Watsonias. Quite possibly the white flower
that Mr. Arderne found among the colony of red-
dish pink ones may have been the only one of its
color among a million, or perhaps ten million, of
its fellows for miles around. But this single atyp-
ical individual chanced to be discovered, and its
progeny to-day are found by thousands, even by
hundreds of thousands, in the gardens and green-
houses, not alone of its native home in South
Africa, but of all parts of Europe and warmer
regions of America.

I myself, as the reader will recall, have raised
these white Watsonias by hundreds of thousands.
Their strains were mingled in the germ plasm of
the quarter million bulbs of this species that I was
obliged to destroy in a single season.

Such are the possibilities of multiplication of a
plant. Such is the geometrical ratio at which the
offspring of a single individual increase if given
encouragement. Boundless, then, are the possi-
bilities that lie before the plant developer who
discovers a single specimen of an aberrant type.
One white poppy among the million yellow ones
might be the progenitor of a race that would dis-
place entirely the whole race of yellow poppies.

What I wish to illustrate at the moment, how-
ever, is not the possibilities of multiplication of

[23]

•§ 2*

S t^I-45

ii

a. >«i

3

SI

ON EXTREME VARIATION

the plant but the interest that attaches to the devel-
opment of unexpected variations. And I repeat
that the possibility of finding a new form in your
flower garden almost any morning will give per-
petual interest to your task, and will come to be a
compelling incentive that will take you to the gar-
den as steel is drawn to the magnet.

To illustrate the possibilities from the case
directly in hand, let us recall the new race of bal-
loon-flowers, the evolution of which we have just
traced. I have said that the experiment began
with the ideal of a balloon-flower of better form,
more graceful placement of flowers, and individ-
ual blossoms larger and of more brilliant color. I
have said also that these ends were in due course
attained, and have traced briefly the steps through
which the new race of perfected balloon-flowers
was evolved.

Now it remains to add that when the experi-
ment was approaching completion, and a new race
of balloon-flowers in many ways satisfactory was
actually in being, I discovered one day among the
blossoms one that had a perfectly regular second
row of petals, instead of the usual single row, or
the irregular so-called double, which had some-
times appeared. Here was an unexpected varia-
tion, which was something that I had not counted
on or considered.

[25]

ON EXTREME VARIATION

But, needless to say, I hailed the new arrival
with delight, and marked it for further education.

If we ask why this second row of petals ap-
peared, the answer can be only a conjecture.
Doubtless some condition of altered nutrition stim-
ulated the plant to this abnormal production. It
is customary to speak of such an anomaly as a
"sport" or mutation. But doubtless these words
beg the question. They name a condition, but do
riot in any way explain it.

It is an observed fact, however, that sudden
variations analogous to this may be stimulated by
a change of climate or a change of soil, as when a
plant is brought from another hemisphere, or by
a surplusage or a shortage of food. It is famil-
iarly known that in a beehive the larva that would
otherwise grow into an ordinary worker may be
made to develop into a queen, that is to say, a
mature female, by forced feeding. In somewhat
the same way a plant that has an excess of nour-
ishment may tend to take on exceptional growth,
and one manifestation of this might be a disturb-
ance of the equilibrium of the floral envelope,
with the production of an unusual number of
petals.

It is known, on the other hand, that a shortage
of food supplies or disadvantageous conditions of
climate may hasten the maturing of a plant, and

[27]

LUTHER BURBANK

cause it to fruit earlier than it otherwise would do.
And any disturbance of equilibrium of this sort
may lead to anomalies in the precise character of
the flower.

Possibly the reason why the petals of the flower
are most likely to be altered as to number, and
also as to color, is the fact that these are about the
newest of all the plant structures. We have seen
that the petals are not themselves essential to the
fertilization of the plant — they are only advertise-
ments to attract insects. They were developed
late in the evolutionary history of the plant, and
their variability is an additional evidence of their
modernity. The fact that so many of our culti-
vated plants have become "double" is in itself suf-
ficient proof of the tendency of the petals to be
modified under conditions of change of climate
and nutrition to which the cultivated plant is
subjected.

But from our present standpoint, what perhaps
is of greatest interest is the fact that when petals
have once shown a tendency to such modification,
this propensity is heritable, and the .progeny of
the plant will reveal some members at least that
show the same characteristic.

Moreover, the "momentum of variation" to
which I have so frequently referred will make
itself felt in the tendency of these variants to take

[28]

A Promising Pupil

Here is a Calendula flower selected from among those
shown in the preceding picture because of its tendency to pro-
duce rudimentary rays in the composite center of the flower. There
is a love of change inherent in the germ plasm of this indi-
vidual, and its progeny will be worth watching.

LUTHER BURBANK

on still wider variation. In other words, the plant
that has developed an extra petal or row of petals
has in its germ plasm factors that will tend to urge
it to the production of still greater modifications
of the floral envelope.

In the case of the balloon-flower, the plant that
had developed a second row of petals, when its
progeny were carefully scrutinized, was found to
have transmitted the anomaly to a certain num-
ber, and among the progeny of these there pres-
ently appeared one that had a third row of petals.
So in the course of comparatively few generations
there had been produced a race of balloon-flowers
that had trebled the number of petals that hith-
erto had been the recognized complement for
flowers of this race.

Multiplication of petals may result, as we have
already noticed, from the transformation of sta-
mens into petals, or it may come about from the
springing into being of new petals de novo, rather
than as modifications of any pre-existing part of
the flower. The latter appears to be the case with
the new rows of petals of the balloon-flower.

Whether the modification will continue until
the balloon flower has a large number of rows of
petals, comparable to those of the double roses,
for example, remains to be seen. But at the pres-
ent stage the flower has a triple corolla, constitut-

[30]

Another Stage of Progress

Here is a calendula flower that has progressed a step far-
ther. It is much larger, and its center is more nearly filled with
ray flowers. It bears but a remote resemblance to its progenitor of the
type shown in the first picture of this series a few pages back.

LUTHER BURBANK

ing a very striking modification. The ultimate
limits of its variation can be determined only by
further series of experiments.

STIMULATING VARIATION

The modification of the balloon-flower has
somewhat exceptional interest, because there is
only a single species of the genus Platycodon, to
which it belongs, anywhere in the world.

In other words, this genus is what is called a
monotype, and it is a well-recognized fact that
flowers belonging to a genus having only a single
species, and even to genera having half a dozen
species, are relatively little subject to variation.
Rightly considered, this is almost axiomatic; be-
cause the very fact that there are many species in
a genus proves that the representatives of that
genus have been variable; else they would not
have developed so many different forms, since all
members of a genus have sprung from the same
ancestry within comparatively recent times.

The balloon-flower has seemingly been isolated
under climatic conditions that have not greatly
changed for a long period and hence it has main-
tained its specific identity, and the type has become
thoroughly fixed. And this fact, as I said, gives
added interest to such an experiment as that just
outlined, which shows how marked may be the
developments that can be produced by selective

[32]

Still Another Calendula Variation

In this specimen the ray flowers are still more crowded,

and the center has been minimized, although still capable of

producing a certain number of seeds. If the seeds were entirely

eliminated, of course the experiment in selective

breeding could go no farther.

LUTHER BURBANK

breeding, even with a flower that tends very
strongly to maintain fixity of type.

But, in point of fact, as we have emphasized
again and again, no flower is so fixed that it does
not vary to some extent; and in the case of the
balloon-flower, it appears that there are modifica-
tions in the type of the plant as it appears in China
and in Japan, that are sufficiently divergent to be
recognized by the botanist as established varieties.
A form from Manchuria also has been modified,
particularly in the matter of the time of blooming,
which is much later than that of the type species.
Also in the matter of color — that most variable of
traits — there is modification, as some varieties are
blue, some bluish white, and some variegated, in
addition to the pure white form.

There was, however, no other color until last
season, when a plant bearing large red blossoms
appeared among a few thousand seedlings which
had been grown from my long-selected varieties.

There is material at hand, then, through which
cross-fertilization may be practiced, with the pos-
sibility of giving the flower still greater impetus to
variation. Until such cross-pollenizing has been
practiced, using varieties of the plant imported
from the most widely spread regions — let us say
races grown in China, in Manchuria, in Japan, in
Europe, and in California — we shall not have

[34]

A Calendula of Real Distinction

This specimen is approaching the limits of variation in

the direction toward which it has been specialized. Note the

fringed character of the ray flowers, and their exceedingly symmet-

trical distribution, like shingles on a roof.

LUTHER BURBANK

tested fully the possibilities of variation of the
balloon-flower.

And indeed, even when these crosses have been
made, there will still remain possibilities to invite
the plant experimenter. For although the balloon-
flower stands in a genus by itself, there are of
course other genera that are not very distantly
related in the Campanula family, to which the
flower belongs. The balloon-flower is often spo-
ken of as the Chinese bellflower, and with entire
propriety, inasmuch as its nearest relatives are
the European and American bellflowers, of which
there are several familiar species, the best known,
perhaps, being the one called popularly the hare-
bell or bluebell, and the Canterbury bell.

It is quite supposable that it might be possible
to hybridize the Chinese flower with one or an-
other of these European or American bellflowers.

And in that event it is not to be doubted that
the hybrid race would show new possibilities of
variation and, by combining ancestral traits that
have not been blended since remote geological
periods, if at all, we should develop among the
progeny of the balloon-flower races that would, in
all probability, differ so radically from the parent
form as scarcely to be recognizable as having any
relationship whatever with the plant with which
our experiment began.

[36]

Extreme Development of Another Type

This calendula, like the preceding one, represents some-
thing like the limits of variation in a given direction; but in
this case the variation is of a different type from the other. Here the
rays are long and graceful, and the flower is less compact in
form, though not lacking in distinction. The two flowers,
like the others shown, have been selected for dif-
ferent qualities from among the progeny
of the same remote ancestors.

LUTHER BURBANK

All of this, of course, is taking liberties with the
future. In the case of the balloon-flower, such
hybridizations have not as yet been successfully
carried out. But in suggesting the possible results
of such potential hybridization, we are merely
drawing analogies from almost numberless experi-
ments with other races of flowers, and we have
every warrant for drawing such conclusions as
those just suggested. Certainly we are justified
in the conclusion that we have not tested to the
fullest the possibilities of variation — that we are
not by any means "getting the utmost variation
out of the flower" — until we have supplemented
the method of selection with that of hybridization.

I may add that there are yet other possibilities
of stimulating variation by chemical treatment of
the developing ovaries of the flower itself; or by
subjecting the plant to unusual conditions of hot-
house temperature; but experiments of this type,
reference to which has been made in an earlier
chapter, have not fallen within the scope of my
own work, and as yet have been carried out only
tentatively by others. So I mention them here only
as suggesting that there are other possibilities so
various and so complicated as to give full assur-
ance that no single line of investigation will ever
reach a stage where it loses interest because it has
brought the investigator to the end of the road.

[38]

IMPROVEMENTS IN THE MUCH
IMPROVED IRIS

AND A FEW OTHER OLD FAVORITES

IF you are disposed to undertake a series of
practical experiments along the lines suggested
in the preceding chapter, it is by no means nec-
essary for you to send to distant countries for the
material.

Of course, the professional plant developer is
always on the lookout for plants from China and
New Zealand and such far-away places. But the
amateur need not be deterred by the difficulty of
securing such materials. It suffices perfectly for
him to go into his garden and begin his experi-
ments with the first flower he chances to find there.

Any old-fashioned flower garden, such as
adorns the door-yards of millions of homes in
America, will furnish abundant material for all
the experiments that any amateur need care to
undertake.

Let me name almost at random a few of the

[VOLUME X — CHAPTER II]

LUTHER BURBANK

common garden flowers that offer interesting op-
portunities for development, and any one of which
will serve quite as well as another for the com-
mencement of your tests of the possibilities of
plant development. Take, for example, the famil-
iar iris, known sometimes as the rainbow plant.
There are specimens of it, in one variety or an-
other, growing in every garden. It makes its way
if given the slightest opportunity, and its some-
what lily-like flower with the graceful recurved
fringed petals has retained its popularity genera-
tion after generation, notwithstanding the coming
of many new favorites.

My own work with the iris has had to do largely
with a Japanese species known as Iris laevigata.
On an acre of damp ground that I have at Sebas-
topol, I raised great quantities of these flowers a
few years ago. The combination of colors was
beautiful beyond description, varying in all shades
of the rainbow. Among the seedlings were num-
bers that produced double flowers, and sometimes
the double ones took on handsome and unusual
shapes, in other cases the anomalies of form were
grotesque and even monstrous, rather than beau-
tiful.

Some of the seedlings produced almost ten
times as many flowers as others, the individual
blossoms being of equal size. Some were tall and

[40]

The Iris

This common and familiar, but very beautiful, garden

flower is one that makes particular appeal to the amateur, and

with which experiments in selective breeding, notably with regard to

color-variation, may be made. This specimen is from Mr.

Burbank's experimental garden in a recent year.

LUTHER BURBANK

lanky and could hardly support themselves when
in bloom. Others were short and compact. The
range of variation was from dwarfed forms of
eight inches to giants of four feet or more.

And that the variation was due to heredity and
not to any environmental conditions was shown
by the fact that the dwarfs and giants might stand
side by side in the same soil and subject to pre-
cisely the same conditions of moisture.

There was not much demand at that time for
new varieties, so I ultimately sold the entire lot of
hybrid Japanese iris as a mixture, without names
or numbers, not taking the time to sort out and fix
different types by selective breeding.

In addition to the Japanese form, I have raised
a great number of other species, including one in-
teresting form in which the seed pods turned out
in a curious way and exposed the orange or scar-
let seeds. This is a species known as Iris foetssis-
sima. I grew this anomalous form extensively to
produce a race that would have seed pods and
seeds that would have better form and open more
fully.

It is not necessary to go into details as to the
score or more of other species that I have grown,
as they all reveal more or less similar tendencies
to variation, and suggest over and over the same
possibilities of development.

[42]

Graceful and Attractive

Mr. Burbank's experiments with the iris have been made

largely with the Japanese variety; but he tells us that there is

ample opportunity to do good and interesting work with the varieties

that are found in any garden. Contrast this specimen, with

its graceful drooping petals, for example, with ones

shown in succeeding pictures. Obviously,

here is ample material for selective

breeding.

LUTHER BURBANK

It does not matter very much, then, what par-
ticular variety of iris is growing in your garden.
Probably there are plants that bear purple flower^,
others with yellow ones, and yet others that are
white. Thi& obviously gives you opportunity for
hybridizing, and there will be abundant interest
in watching the results of the blending of different
colors.

If at the same time that you are crossing the
iris of different colors you save also seed from
other plants, or from different flowers on the same
plants, that are not crossed, you will be able to
check the results of your experiment, and will find
yourself launched at once into an investigation
that offers fascinating possibilities. It should be
explained, however, that the cross-pollenizing of
the iris presents complications which will not be
solved unless you make a very careful inspection
of the flower.

The stigma of the flower has a little lip under
the unique petaloid pistils, very different in ap-
pearance from the organs of most other flowers.
If you examine it closely you willl see that the lit-
tle shell-like lip that projects is adjusted in just
the right way to scrape pollen off the back of a
bee as it enters the flower, or similarly from the
head of a humming-bird. The arrangement is
such that the bee or humming-bird will come in

[44]

A Broad-Petalled Iris

The form of the iris is characteristic, and there is not as
wide variation in this regard among the different varieties of
this tribe as among many others. Yet the form of the petals may be
very conspicuously modified, as this specimen shows. In-
teresting studies in form variation might be made by
crossing such a specimen as this with the
one shown in the preceding picture.

LUTHER BURBANK

contact with the pollen of an individual flower
only after it has passed the pistil, and the protect-
ing sheath prevents the deposit of pollen as the
insect or bird leaves the flower. Thus it is insured
that self-fertilization will not take place.

While the flower is, as I said, complex in this
regard, nothing more is necessary than to study
its mechanism attentively, pulling to pieces two or
three blossoms to see just how the pollen must be
deposited. After that you will experience no diffi-
culty in cross-fertilizing the iris, and the results of
your work are sure to be of interest.

FOUR-O'CLOCK AND COLUMBINE

The familiar four-o'clocks are all natives of
America, but most of them had their original home
in the sub-tropical and tropical portions of our
continent. There is one, however, that is native
to California, and various species made their way
to the gardens even far to the north a century or
more ago, and are now grown everywhere.

The most striking peculiarity of the four-
o'clocks is their tendency to combine different
colors in the same flower in peculiar patterns.

We have seen a great deal of color variation
among flowers. We have seen numberless in-
stances in which blossoms of the same species may
be in one case red, in another pink, in a third yel-
low, and in a fourth white. We have seen also

[46]

ON SOME COMMON FAVORITES

some instances of the mingling of different colors
in the same flower, notably with some of the dah-
lias. But our attention has been called to no
flower that mingles the colors in quite so anom-
alous a way as is characteristic with the four-
o'clocks. For these blossoms, seemingly unable
to decide between different colors, have hit upon
a compromise of arranging the colors in definite
stripes, which give the tubular corollas a very
curious and characteristic appearance.

In a lot of seedlings, supposedly of the same
variety, the stripes may come in various widths of
white, crimson, and yellow. Even when the seed
is saved from a single plant, there will be great
variation among the seedlings, in some the wide
white stripes predominating, in others the crim-
son, and in yet others the yellow. Again, some of
the flowers may come pure white, or yellow, or
crimson, or pink, quite without stripes; or perhaps
half of the blossoms on a given plant will be one
color and half another.

It is obvious that a plant showing such wide
variation does not call for hybridization to stim-
ulate variation. The mingling of hereditary
strains is already sufficiently complex, and you
will find quite sufficient occupation in attempting
to sort out new races of a good color or combina-
tion of colors, and in fixing a dozen of them so

[47]

A Spectacular Iris

Color variation is, of course, the most conspicuous char-
acteristic that will appeal to the amateur in the case of the iris.
There are purple iris and yellow ones and white ones in almost any
garden, and these may be combined in endless ways.
Here is a specimen that shows an interesting
and spectacular color-blending.

ON SOME COMMON FAVORITES

that they will come reasonably true to type. If
you succeed in accomplishing this, in the course of
a few seasons, you will have performed an experi-
ment that you will find full of interest, and your
task will not have been carried out without giving
you very suggestive sidelights on the problem of
heredity.

It is, in any event, a very curious anomaly that
a plant should so have assorted its hereditary fac-
tors that they adopt this compromise. And your
investigation, which endeavors to determine how
accurately the tendency to striping is dependent
on particular combinations of hereditary factors,
will not only prove interesting, but may lead to*
valuable revelations. The entire problem of the
study of heredity of color, notwithstanding the
attention that has been given it, still bristles with
unanswered questions. Your experiments with the
old-fashioned four-o'clock may serve to give you
answers to some of them.

A somewhat simpler but perhaps no less inter-
esting problem in color heredity may be taken up
in connection with the equally familiar columbine.

There are thirty or more species of the genus
Aquilegia, or tribe of columbine, and examples of
one or two of the more common ones are sure to
be found in your garden. At least you can get
seeds from which to grow them at any florist's.

[49]

LUTHER BURBANK

I have always been fond of the columbines
because of their numerous species, and their wide
range of color variation; also because of the curi-
ous shape of the flower and the tendency of the
spurs to vary greatly in length, as well as in their
tendency to open out in some cases, and in others
to remain partially closed. There is, indeed, one
old cultivated variety which has lost the spurs
altogether.

I made at one time some interesting experi-
ments with this spurless kind of columbine, cross-
ing it with many others, especially with one known
as the coemlea, which has very large flowers of
beautiful shades of blue. The hybrids of this spur-
less form with the other species produced beau-
tiful large climatis-like flowers, some of them
three or four inches in diameter.

Perhaps the most interesting feature of the
experiment was that the hybrids were entirely
spurless. This shows that the condition of spur-
lessness, which is an anomaly presumably of re-
cent origin, inasmuch as the spurs are a character-
istic feature of the flowers of the wild columbines,
acts as a dominant factor in heredity. This, of
course, is what should be expected if it be true
that the newly developed characteristics of a plant
are dominant over the older ones. But the case of
the columbines furnishes another interesting cor-

[50]

A Round-Petalled Iris

Contrast this speciiren, with its almost circular lower
petal with the ones shown in succeeding pictures. The char-
acteristic iris traits are present throughout; but the modifications in
form of petals, ard in the relative sizes of the dif-
ferent petals, are very conspicuous.

LUTHER BURBANK

roboration of this interpretation of Mendelian
heredity.

In the course of other experiments with the
columbines numerous other species were brought
into the combination through successive hybrid-
izations, until my columbine colony carried the
strains of more than a dozen recorded species. A
most beautiful lot of hybrids resulted. Their vari-
ous members revealed nearly all the colors of the
rainbow. I introduced them to the trade as mixed
varieties, as it did not seem to be worth while to
fix the different types. On the contrary, the vari-
ety of blossoms seemed to be considered an
advantage.

But, in point of fact, even if it had been desired
to fix the new types, it would have proved exceed-
ingly difficult to do so. When you have two or
more species of columbine in combination, the
hereditary complications are comparable to those
in the gourd family, to which we have had occa-
sion to refer. It seems as if every member of a
fraternity differs from all other members, and you
cannot be at all sure as to what results you may
attain by sowing seed from any individual plant.

But these complications result in part from the
fact that the different columbines are so easily
crossed by the bees. This is a case where there is
no difficulty in effecting hybridization; the diffi-

[52]

An Iris with Pointed Petals

Here the petals have been modified so that they are
pointed instead of round, and their texture is quite different
from that of specimens shoivn in the preceding pictures. Such mat-
ters as these have great interest for the gardener, but are prob-
ably not vital from the standpoint of the economy of the
plant itself; hence they are particularly subject to
variation, affording the plant breeder pre-
cisely the opportunity he is seeking.

LUTHER BURBANK

culty is to prevent crosses that are not desired. If
the plants are shielded from the visits of the bees,
and careful hand pollenizing is effected, there is
no great difficulty in combining the different forms
in such a way as to get definite results, and the
hybrid forms may be fixed by careful selective
breeding.

Of course, when you deal with a spurless form,
if the individuals that you use are themselves
hybrids of the first generation of a cross between
a spurred and a spurless variety, their progeny,
when they are crossed with a spurred variety, will
be in effect second generation hybrids and only
half of them will be spurless. But this, again,
merely illustrates the familiar segregation of char-
acters and the reappearance of the recessive trait
—in this case the spurred condition — in a rather
definite proportion of the second generation
progeny.

Another anomaly among the columbines that
offers good opportunity for experimental tests is
furnished by the double varieties. I used to notice
that if you crossed a double and a single one, you
are about as likely to get a double as a single.
Here, again, it would appear that the double con-
dition of corolla acts as a Mendelian dominant
factor, and that the strains with which I worked
were themselves mixed.

[54]

A Difficult Flower to Cross-Pollenize

To casual inspection, the iris does not appear to be a
perfect flower. That is to say, it seems to lack stamens and
pistils of the ordinary type. In point of fact, the iris has organs of
fertilization that are quite petal-like in appearance, arranged
in such a manner as to provide against self-fertiliza-
tion. But intelligent inspection will enable
the would-be pollenizer to solve
their mysteries without great
difficulty.

LUTHER BURBANK

All in all, then, the columbine offers most in-
teresting possibilities for the experimenter who
likes to test for himself the principles of heredity.
In the matter of color, there is the widest variation,
some of the familiar forms being blue, others red
and yellow. The curious spurs that characterize
the flower, and the fact that some varieties lack
them, furnish tangible features that may be tested,
and the single versus the double corolla constitutes
a third feature that is also susceptible to definite
observation and record.

So the experimenter who will work with a
small number, differing as to characteristics of
color and spur and doubleness, has opportunity
for watching the interplay of hereditary forces;
observing the dominance of certain hereditary fac-
tors, and the recessiveness of their opposing fac-
tors; and finally the segregation of the different
characters and their reassembling in new com-
binations in the second generation, that will test
his knowledge of the principles of heredity to the
utmost, and at the same time will give him definite
ideas about the practicalities of plant develop-
ment that will be at once interesting and valuable.

Meantime the experimenter may introduce
problems of far greater complexity if he so desires
by mixing larger numbers of the plants somewhat
at random, and allowing them to be cross-fertilized

[56]

ON SOME COMMON FAVORITES

by the bees. In this way he may secure, as I have
done in some experiments, columbines of the most
wonderful variety. In some of the mixed hybrid
colonies, the blending of hereditary factors was
so complex that among ten thousand plants there
would be perhaps not five hundred that could be
classified as approximately identical with one
another, or as conforming to a specific type.

In other words, there \vould be perhaps nine
thousand five hundred individual plants, each of
which might be said to constitute a distinct
variety.

In the course of these experiments I made per-
haps ten thousand careful hand pollenations be-
tween different specimens of these variant hybrids,
and, needless to say, secured plants with excep-
tional blossoms of many kinds.

A similar line of experiment is open to anyone
who has the smallest plot of ground in which he
can grow a few scores of columbines.
CAMPANULA AND COREOPSIS

If you were to seek experiments of a still sim-
pler character, you might do well to consider the
beautiful campanula, known familiarly as the
bluebells of Scotland.

These are hardy flowers, growing wild in great
profusion, even far to the north. On a trip to
Canada a good many years ago I was delighted to

[57]

An Ingenius Mechanism

The stigma of the iris has a little lip under the unique
petaloid pistils, adjusted in just the right way to scoop the
pollen off the back of a bee as it enters the flower, or from the head of
a humming-bird. The bee or humming-bird will come in con-
tact with the pollen of this flower only after it has passed
the pistil, and the protecting shelf prevents the de-
posit of pollen as the insect or bird leaves
the flower. It is a most ingenius and
interesting arrangement.

ON SOME COMMON FAVORITES

see great fields of companula as far north as
Alberta. They are said to grow even in Siberia.
So whatever the location of your garden, you will
probably have no difficulty in raising bluebells.
The plants, to be sure, are somewhat subject to
the attacks of fungus pests and insects, but aside
from this difficulty they are easily grown. It goes
without saying that a flower that has become
famous as the "bluebell" is generally blue in color.
Yet it is by no means unusual to see specimens that
are pure white. And it is this variation that gives
opportunity for some simple experiments in cross-
breeding.

Nothing more is needed than to secure plants
of the ordinary blue variety and others that bear
white blossoms. The campanulas are easily
crossed, and you will have opportunity to test the
color variation in heredity in some of their sim-
plest relations. There are, to be sure, many spe-
cies of campanulas, and it is true that the garden
varieties are likely to have been hybridized. I
have, for example, raised seedlings from the white
campanula, Rotundiflora, without securing any
white ones. It will be necessary, therefore, for you
to test your varieties by raising plants of uncrossed
seeds at the same time that you are making the
cross-pollenations. But this complication will only
add interest to the experiment.

[59]

LUTHER BURBANK

The many tribes of coreopsis give opportunity
for experiments of equal interest. These plants
are composites, and in hybridizing them it will be
necessary to use the method detailed in our story
of the dahlia, washing away the pollen before
applying pollen from the other flower.

The different members of the family vary in
color from deepest purplish crimson to light yel-
low and white. There are numerous species under
cultivation, and there are wild ones growing as
roadside weeds that are readily accessible. The
variability of the different races makes them an
interesting race with which to work.

My own work with the tribe has included a
good many species, the most important of which
is the one known as the Coreopsis linceolita. The
experiments look to the increase of the number
of florets, as well as to the size of the flowers and
abundant bearing. I also had in mind improving
the form of the plant. There was no great diffi-
culty in doubling the size of the flower, and in the
course of four years, working with seed purchased
in the common market, varieties were produced
that were considered worthy of introduction, and
that were distributed by several leading florists.

The developed varieties had exceptional value
because of the large size of the flowers and of the
small center; also because of the long stems, mak-

[60]

A Luxurious Type

There is something peculiarly oriental and luxurious
about the appearance of this particular variety of Burbank iris;
the idea being carried out by the richness of coloration and the softly-
flowing contour of the petals. In point of fact, however,
the oriental iris is of a somewhat different type,
as will be seen in succeeding pictures.

LUTHER BURBANK

ing it a good flower for cutting. A fault of many
of the annual varieties is that they have small,
weak stems.

As to all of these matters, the amateur can work
by selection and by hybridizing. The wide range
of color variation affords a ready guide in hybrid-
izing experiments, and the ease and certainty with
which the plants can be grown from seed adds
greatly to their utility from the standpoint of the
amateur.

SHOOTING STAR AND SALVIA

A really fine plant that offers opportunity for
improvement, yet which has been little worked
with, is the Shooting Star, sometimes called Amer-
ican cowslip, a member of the primrose family,
classified under the genus Dodecatheon.

There are sixteen or eighteen species described
in botanical literature, yet so great an authority
as Asa Gray thought that all the Dodecatheons in
the world should be classified as one species.
There are remarkable variations in size and color,
however, yet the varieties are sufficiently fixed to
offer good opportunity for experiment, and at the
same time are closely enough related to that they
may readily be crossed.

The flowers of the various types show the wid-
est variation — dark purple, crimson, rose, white,
spotted, cream color, and yellow. There is oppor-

[62]

A Japanese Iris

Mr. Burbank's experiments, as already mentioned, have
largely had to do with the Japanese iris. He raised great quan-
tities of them at Sebastopol a few years ago. The combinations of
colors are beautiful beyond description, and they vary in all
shades of the rainbow. Sometimes the double ones take
on handsome and unusual shapes. These are
typical specimens of a more usual form.

LUTHER BURBANK

timity for sorting out individual colors and their
fixing through selection; and, on the other hand,
for the combination of colors to produce new
shades.

The plants are handsome, and they furnish
admirable material with which to work, not
merely by way of gaining experience, but also with
the possibility of producing worthy new varieties.

The Salvia are members of the mint family.
There are many species, showing a wide range of
variation. The commonest one is known in every
garden for its brilliant red flowers borne in such
profusion as to make splendid masses to group
along walls or as borders. There are other sal-
vias, however, that have charming light blue flow-
ers. The plant in the ordinary gardens is grown,
of course, only for its flowers, yet there is a species,
known as Salvia sonomensis, or Salvia ramona,
that is abundant on some of the hillsides in Cali-
fornia, and that is to all intents and purposes iden-
tical with the cultivated sage. Its foliage has the
exact flavor of that of the cultivated plant. I have
at times thought of growing it to see if there could
not be developed from it a sage that would be
more valuable for seasoning than the one under
cultivation. The common sage runs into numer-
ous varieties, some woolly leafed, some golden
leafed, and some with tri-colored leaves.

[64]

Seedling Japanese Iris

This is one of a multitude of variants among the seed-
lings of the Japanese iris. It is probable that these plants were
stimulated to vary by the change of climate and soil. We have seen
numerous illustrations of similar effects of a changed environment.

LUTHER BURBANK

It is possible that by hybridizing this plant with
the wild variety improvement would be made in
the unique quality for which its leaves are prized.

From the present standpoint, of course, our in-
terest in the salvias concerns their flowers. I have
done a great deal of work with various members
of the family, both in the way of selection and of
hybridization. The plant is tremendously vari-
able, even within the same species, and the various
forms run more or less together so that it is diffi-
cult differentiating them botanically. But the con-
trast between the species bearing blue flowers and
the familiar garden plant with its scarlet blossoms
is striking enough to challenge the attention even
of the least observant.

The fact that the various species can readily be
hybridized, while at the same time they show such
variation as to color of blossom, gives them obvi-
ous interest from the standpoint of the amateur
plant experimenter. It should be noted, also, that
there are some salvias with white leaves, one of
these having foliage so thoroughly covered with a
white thick wool-like growth that the leaves make
excellent pen wipers. The experimenter who
works with one of these varieties could doubtless
develop interesting modifications of leaf through
selection alone, and, of course, hybridizing meth-
ods could be utilized to accentuate the variation.

[66]

More Japanese Visitors

These flowers suggest the range of variation in form and

contour and color among seedlings of the Japanese iris. Many

of the variants are beautiful, and some are grotesque, and all of them

are highly interesting from the standpoint of the plant developer.

LUTHER BURBANK

A plant that is exceptionally interesting because
of the work that has been done with it in recent
years is the familiar evening primrose (Oeno-
thera).

Mention has been made in another place of the
famous work of Professor DeVries, which fur-
nishes the foundation for his celebrated theory of
mutation. It will be recalled that Professor De-
Vries found specimens of evening primrose that
departed so widely from the form of their parent
as to seem to constitute new species. The question
whether these mutations were of unexplained
origin, or whether they were really due to hybrid-
ization, is still perhaps an open one. But, in any
event, the use made of them by Professor DeVries
called particular attention to this plant, and has
given it a place quite apart among flowers of field
and garden.

There are many species of evening primrose,
and the tendency to vary among them is marked.
Variation, however, does not extend to the flower.
There may be all manner of modifications of stem
and leaf, but the typical blossoms of the evening
primrose are of a pleasing pale lemon yellow.
MY PRIMROSE EXPERIMENTS

I have experimented with the primroses, cross-
ing them quite extensively. One form that was
received from the mountains of Chile has given

[68]

Unnamed Flowers from China

Here are blossoms of an unknown species of flower,

obviously closely related to the iris, the bulb of which was

sent to Mr. Burbank from China. The gardens at Santa Rosa teem

with nameless exotics, all of which are sure to be tested

as to their propensities and capacities.

LUTHER BURBANK

some interesting results through selection, in that
it now produces blossoms, a single petal of which
would cover the entire blossom of any of tne larger
primroses under cultivation. The flower itself is
sometimes six inches or more in diameter. A bed
of these plants reminds one of a lot of handker-
chiefs spread out on a lawn, as the blossoms are
somewhat square with rounded corners. A new
crop is produced each morning throughout the
entire summer.

The plant itself is somewhat trailing, and about
two feet to two and one-half feet in diameter. It
is a perennial, though it commences to bloom quite
early in the season.

This large flowered variety has been produced
by most rigid selection for size, form, and white-
ness and substance of flower, and it far surpasses
all other members of the genus in size and beauty.

I have hybridized this Chilean race with the
common Oenothera acaulis, or Taraxaci folia, and
produced a large number of intermediates, from
the best of which I have made selection. These
hybrids seem to come absolutely true in the sec-
ond generation, so far as foliage is concerned,
being in all cases intermediate between the two
species. This is perhaps what would have been
expected in a member of this race, in view of the
observations of Professor DeVries. The plant

[70]

Selected Chinese Iris

Note how widely this flower differs in form and general

appearance from the iris shown in earlier pictures. Such

variations are always a source of gratification to Mr. Burbank, as they

furnish obvious material for crossbreeding experiments.

Interesting tests of the present flower have

been made in that connection.

LUTHER BURBANK

seems to have an exceptional propensity to form
new types.

This, of course, is precisely the characteristic
that gives the plant interest from the standpoint
of the amateur experimenter. So a plot may very
well be set aside in the flower garden for some
evening primroses of two or three species. Hy-
bridization will readily be effected by the insects,
if the experimenter does not care to take the trou-
ble to hand-pollenize the plants, and the produc-
tion of some interesting new forms may fairly be
counted on.

I will name only two other common plants from
among the almost numberless ones that might be
selected, as offering advantageous material for
selection by the amateur experimenter. But these
are about the commonest of all, and in some re-
spects among the most beautiful and interesting—
the golden rod, and the aster. These plants are
almost universally associated when growing wild
in the field, and their blossoms form so beautiful
a contrast that the two may very well be trans-
planted to the garden together.

I have experimented quite extensively with the
goldenrods, and at the same time made a collec-
tion of the native asters. And while the two plants
are so very different, the fact that they blossom
together late in the fall and harmonize so beau-

[72]

An Improved Evening Primrose

Mr. Burbank has worked extensively with the evening

primrose. This one is a species from South America, which

attains altogether unusual dimensions, some specimens suggesting a

small handkerchief spread out on the foliage. Mr. Burbank's

experiments with the evening primrose have convinced

him that Professor DeVries' celebrated mutants of

this tribe are in reality hybrid forms.

LUTHER BURBANK

tifully in the landscape, makes it worth while, as I
have just suggested, to work on the two in com-
bination.

The golden rods are of so many species and so
variable that they tax the skill of the botanist. To
differentiate between them accurately is a task
lying far beyond the skill of most amateurs. But
for that matter, it is my observation that the dif-
ferent species hybridize so freely when growing
wild that the specific lines are thoroughly broken
down.

Any botanist who pretends to fix hard and fast
lines between the different species of golden rods,
and does not take account of the hybrids, which
are even more numerous in many localities than
the parent forms, will not gain a very adequate
idea of the golden rods as they actually grow.

Any species of golden rod will serve the pur-
pose of the experimenter. But, of course, it is
desirable to have a number of species, and it is
obviously worth while to make careful selection
in deciding which ones to transplant to your gar-
den. I have spent many days on a few acres of
ground, searching among the multitudes of golden
rods for the most beautiful individual specimens.
From these selected seed was collected, or the
roots themselves dug, to furnish the basis for
further experiment.

[74]

A Spray of Goldenrod

There are numerous species of goldenrod and these grow
in neglected fields almost everywhere. Mr. Surbank found that
the different species constantly hybridize in a state of nature. He
suggests that the goldenrods are very interesting flowers for ex-
periments by the amateur in crossbreeding and selection.

LUTHER BURBANK

Some of the wild forms seem almost perfect,
yet when taken under cultivation and carefully
selected they prove susceptible of betterment.

The hybrids, in my experience, are not as vari-
able as might be expected. But this is no doubt
because the plants with which we worked were
themselves hybrids. In point of fact, one can sel-
dom be sure, in working with the golden rods, that
one is working with pure species.

But such complications, of course, give added
interest to the work of the plant developer after
he has the fundamentals of the method fairly in
hand. And I can think of few problems that would
be more interesting than to attempt to untangle
some of the hereditary complications among the
golden rods. The fixing of types by selection; the
improving of the best existing ones; and the devel-
opment of new types by hybridization — these are
all methods that offer opportunity for fascinating
experiments.

Whoever takes the trouble to make friends of
the golden rod is not likely to regret his experience.

— Any old-fashioned flower
garden will furnish abundant
material for all the experi-
ments that any amateur
need care to undertake.

THE TIGRIDIA AND SOME
INTERESTING HYBRIDS

NEW CHARMS IN FAR AWAY FLOWERS

ABOUT a quarter of a century ago I com-
menced cultivating and crossing all the
Tigridias, or Tiger Flowers that were then
offered by any seedsman or nurseryman anywhere
in the world.

I also secured all the species of the allied genus
Ferraria that I could obtain and cultivated them
for the purpose of hybridizing them with the tiger
flowers. The Tigridias are natives of subtropical
and tropical America, ranging from Mexico to
Peru and Chile. The Ferrarias are from the Cape
of Good Hope, and are represented by a number
of species.

Both tribes belong to the Iris family, and the
two forms are so closely related that by some
botanists they are regarded as properly falling
within the same genus.

My own experiments, which show the ready

[VOLUME X — CHAPTER III]

LUTHER BURBANK

hybridization of the various Tigridias and Ferra-
rias, suggest that they are closely related. Yet the
fact that they are indigenous to different conti-
nents shows that they have been separated for a
very long period of time, although doubtless of
common ancestry.

The students of geological botany tell us that
there must have been a great mass of land in the
southern hemisphere at one time on which races
of plants developed that subsequently were iso-
lated on the land masses that are now known
respectively as South America, Africa, Australasia,
and New Zealand. At that remote period the
Tigridias and Ferrarias were doubtless of one
stock, and the fact that their descendants of to-
day retain such elements of affinity as to puzzle
the botanists and to serve well the purposes of the
hybridizer gives another illustration of the won-
derful pertinacity with which the characteristics
of a plant are sometimes transmitted through
almost numberless generations without radical
transformation.

It is little wonder that the earlier biologists,
before the coming of Darwin, when confronted
with such observed cases of affinity between races
that must have been separated for countless thou-
sands of years, were strong in their faith in the
fixity of species.

[78]

The Interesting Tigridia

The tigridias are very interesting lily-like flowers from the
tropics. Mr. Burbank has experimented with them very extens-
ively, both by way of selection and through crossbreeding. Some of the
results of these experiments are shown in succeeding pictures.

LUTHER BURBANK

Yet the facts of variation, even within a few
generations, are too obvious to escape attention.

And the compromise has been found, as every-
one knows nowadays, in a recognition of the fact
that time is long, and the further fact that natural
selection may be instrumental in maintaining the
fixity of a race, provided the environing conditions
are unchanged, just as it may be instrumental in
somewhat rapidly changing the form of a race
when the environing conditions have altered.
HYBRIDIZING THE TIGER FLOWERS

From the outset I found that the various tiger
flowers throve in my gardens, particularly in the
sandy land at Sebastopol and in sandy beds
especially prepared for them at Santa Rosa.

As I have already said, I began at once crossing
and hybridizing the various species and varieties,
and of course carried out selection among the seed-
lings and made new crossings, according to my
usual custom. The type species with which the
experiments began was the Tigridia pavonia, of
which there are numerous varieties. Another form
known, as the Conchiflor or Shell flower was uti-
lized, and subsequently the T. buccifera, a form
more recently introduced from Mexico.

An especial effort was made to introduce also
into the combination the strains of a plant of yet
another genus, the Herbertia platensis. This is a

[80]

ON THE TIGRIDIA

tall-growing plant bearing close resemblance to
the Tigridias, and by some botanists classified with
them. It has pale blue flowers marked with yel-
low, and the specimens are of a somewhat different
structure from those of the Tigridia, though the
bulb and general growth of the plant are similar.

I particularly desired to introduce strains of
the Herbertia platensis, because this is a very
strong-growing plant, and its vigor and health
would be of great service in giving hardiness which
is the one thing that the Tigridias more especially
lack.

In particular, the bulbs of the tiger plant are
difficult to keep over winter, and especially subject
to decay from exposure to air and to the attacks
of aphids when stored.

But much to my disappointment I was never
able to effect hybridization between any of the
Tigridias, either pure bred or hybrid, and the Her-
bertia. The experiment was made over and over,
and in every case it was without result.

Meantime, however, there was no difficulty
whatever in hybridizing the ordinary cultivated
strains of Tiger Flowers among themselves and
with some of their South African relatives. And
the results of such hybridizings were manifest
almost from the outset.

One of the most striking modifications shown

[81]

Hybrid Tigridias

The word tigridia or tiger flower, would suggest a striped
flower, whereas in point of fact this flower is spotted. Mr. Bur-
bank suggests that the word "leopard" or "panther" would have been
more appropriate; and that the term "jaguar flower" would
have been still more significant, inasmuch as the tigridias
come from South America, the home of the jaguar.
The specimens here shown are hybrids of a
very interesting type,

ON THE TIGRIDIA

by the hybrid Tigridias was the development of
varieties having striped flowers. It might very
well be expected that a "tiger flower" would be
striped. But in point of fact the native Tigridias
are spotted and never striped. They might with
much greater propriety have been named after the
leopard or panther, or better yet, considering their
origin, after the South American jaguar. But the
botanist who originally named them seemingly had
rather vague notions as to the markings of the coat
of the tiger, or else considered it sufficient that the
flower itself wears a yellow mantle with dark
markings.

In any event, there is something about the
aspect of the flower that makes the name "tiger
flower" seem not inappropriate.

And the propriety of the name becomes quite
beyond challenge when my new hybrid varieties
are under observation. For these are striped in a
way that is very striking. Quite aside from its
suggestions as to one feline or another, however,
the new hybrids are flowers of great beauty and
interest and differ conspicuously from any of the
parental forms.

Not only are the markings thus conspicuously
altered, but the flower itself is greatly increased
in size. The tendency to freedom of bloom is
accentuated. Moreover the hybrid plants have

[83]

LUTHER BURBANK

gained greatly in vigor of growth, in hardiness,
and in resistance to disease.

The colors of the new flowers are conspicuously
brightened. The striping is usually crimson on
white, crimson on yellow, or yellow on crimson.
In addition to presenting these stripes, which are
quite unlike any marking of the native Tigridias,
the hybrid flowers generally retain the dotting at
the center that characterizes the tribe in its origi-
nal form. But these dottings are greatly increased
in size. In some instances, on the other hand, the
dottings are partially or entirely eliminated.

The original types of these very striking new
forms of Tiger Flower were readily fixed so that
they breed absolutely true from the seed.

It was possible, however, to increase the size
of the flower by selection, and this increase in size
was a permanent acquisition; also to add brilliance
with new combinations of colors.

And of course the hybrid plants thus perfected
exceed greatly the size of any plants that could
have been developed by mere selection without
crossing.

UTILITY AS WELL AS BEAUTY

The new tiger plants, although still lacking
something of hardiness, were greatly improved in
this regard over their ancestors.

Most of the old tigridias, as I have said, are

[84]

Another Hybrid Tigridia

None of the tiger flowers are striped, which seems to
make their name inappropriate, as already suggested; neverthe-
less there does seem to be something tiger-like about this richly ca-
parisoned and oriental-seeming flower. It is rather curious to
reflect that the spots on the flower are intended to make
it conspicuous, whereas the striped coat of its
namesake is calculated to make the animal
invisible in the jungle.

LUTHER BURBANK

quite subject to insects and disease. The hybrid
forms are much more resistant. There is also a
greater power on the part of the new plants to
stand sunshine. The old tigridias sometimes with-
ered under the influence of the sun. This might
not at first thought be expected of a tropical plant,
but it should be recalled that the growth of vegeta-
tion in tropical regions is so luxuriant that low-
growing plants of this order are not usually sub-
ject to the direct rays of the sun throughout the
day.

It goes without saying that the bulbs of the
new tiger plants were improved in proportion to
the stalks and flowers. The bulbs of the tiger
plant are elongated and tunicated, and multiply
by division somewhat after the manner of the
hyacinths, tulips, and the allied races in general.

The bulbs of the new hybrid tigridias were
doubled in bulk, and in some cases quadrupled, as
contrasted with the parent forms. Like the some-
what similar bulbs of the gladiolus, they may best
be kept in the ground over winter here in Califor-
nia, instead of being taken up and stored as is
necessary in colder climates.

The development of the bulbs of the tigridias
has not been at all a matter of accident. At all
stages of the experiment in hybridizing and selec-
tion, I have paid the most careful attention to the

[86]

Variant Hybrids

It will be seen that the different tigridias hold rather
closely to the same characteristic type of flower. There is,
nevertheless, a good range of variation as to size, precise contour of
petals, and color. Of course the hybrids show combinations of
characters that are not united in any single one of their
parents. There is the usual tendency to the segre-
gation of these characters into many new
groups in the second generation.

LUTHER BURBANK

condition of the bulbs, selecting always those that
were largest, firmest and soundest. And the reason
for this was not merely that such bulbs usually
produce the best flowers, but also that it is worth
while to improve the size and quality of the bulbs
quite on their own account.

The particular reason for this is that the bulbs
of the Tiger Plant are edible. When cooked like
potatoes, or made into a stew, they constitute a
really delicious vegetable.

To my taste the bulb of the tiger plant is at
least the equal of any vegetable under cultivation.
It is also highly nutritious. I am not sure that it
has an equal among the vegetables of our gardens
in its combination of nutritiousness and appetizing
flavor.

These very qualities lead to its destruction by
all kinds of animal and insect life, like the Lilium
Brownii, which has no bitter principle, containing
sweet and nutritious matter, and which also is
attacked and appropriated by insects and other
creatures.

As yet the tigridia is too tender to gain a place
in the vegetable garden on a footing with the
potato and allied bearers of bulbs and tubers. But
when through further breeding experiments, it
has been rendered more amenable to general culti-
vation, its bulb being at the same time still further

[88]

Seedling Tigridias

The wild species of ttgridias of course breed true from

the seed. But, equally of course, the hybrid forms cannot be

expected to do so. So there are fascinating possibilities of variation

among the progeny of any hybrid. Yet even the most widely

varying specimen is at once recognizable as a tigridia.

LUTHER BURBANK

increased in size, the tiger plant may come to be
valued for its edible bulb quite as highly as for its
beautiful and spectacular flower.

MULTIPLICATION BY BULB DIVISION

The habit of storing nutritious matter in its
bulb, and the further habit of producing collateral
bulbs from which new stalks will grow, so that the
plant multiplies indefinitely in this way, is charac-
teristic, as everyone knows, of a large number of
plant families, many of which have come within
the scope of our studies.

The phenomenon of bulb division, indeed, is so
familiar to everyone who has experimented in the
vegetable or flower garden as to take its place
among those familiar matters of fact that call for
no comment.

Yet if we consider the matter thoughtfully it
will be clear that this habit of putting forth offsets
from a bulb as the basis for the development of
new plants is an altogether extraordinary phenom-
enon— quite as mysterious, indeed, as the produc-
tion of the seeds that bear the complex hereditary
factors and transmit the qualities of a race of
plants from one generation to another.

There is, in point of fact, no fundamental dif-
ference between the production of new plants by
bulb division and their production by seed, except
that in the latter case there is opportunity for the

[90]

ON THE TIGRIDIA

union of two different racial strains, one borne by
the pollen and the other by the ovule. This, to be
sure, is a difference that has very important prac-
tical bearings, inasmuch as the union of two dif-
ferent hereditary strains gives opportunity for the
blending of hereditary factors and their re-com-
bination, thus compelling variations that furnish
the basis for natural or artificial selection, through
which new races are developed.

All this needs no explication here, as our
earlier studies have made it perfectly familiar.
But what I wish now to emphasize is the fact that
the bulb that produces a new plant carries the
hereditary factors of the parent plant substantially
as they are borne by the ovule or the pollen gram
that the same plant puts forth on its aerial stalks,
and exactly as the bulb of any plant — in fact, the
bulb of any plant is only a fat, immature, under-
ground bud.

If the ovule could develop without being
fertilized, or if the pollen could grow into a plant,
the result in either case, we may reasonably
assume, would be a reproduction of the plant
closely similar to the parent form, just as the
aphids and the bees when parthonogenetically
produced, and in a few instances of plants, for
example, the violet. Yet there are differences
between the different pollen grains and between

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ON THE TIGRIDIA

the different ovules of the same plant, as demon-
strated by the fact that flowers, for example, of
different hues may be borne on plants grown from
a single seed pod.

So if we are to present the matter quite in its
true light we should say that the aggregate pollen-
product and ovule-product of a plant must be con-
sidered as representing the personality — that is to
say, the hereditary complex — of the plant.

No single pollen grain and no single ovule
contains representatives of all the types of heredi-
tary factors that are present in the germ plasm of
the plant as a whole.

Stated otherwise, the pollen grains and ovules
are very specialized and concentrated portions of
matter, each of which contains a similar equip-
ment of the most fundamental of the hereditary
factors, but each of which contains a somewhat
different assortment of the less fundamental ones.

All the plants that grow from the seed of a
tigridia, for example, will be unequivocally tigrid-
ias in stem and leaf. But there will be minor dif-
ferences among them as to details of size, as to
freedom of flowering, as to precise size of flower,
and as to the exact distribution of the color
markings.

As a matter of course, when the seeds are the
product of cross-pollenizing, the offspring, repre-

[93]

Bulbs of the Tigridia

This large tigridia bulb is developing a cluster of small
offshoots. Each of these little bulbs will produce a plant dupli-
cating almost absolutely the original parent form. There is no such
range of variation among plants grown from bulbs as among
those grown from seeds. The bulb of the tigridia
has exceptional interest because it is edible.

ON THE TIGRIDIA

sen ting now two parents, will show a still wider
diversity of hereditary traits.

Meantime, turning attention again to our bulb,
we find that this structure represents the parent
form with much greater fidelity. As nearly as
there can be identity between two different living
things, the plant that grows from any offset of the
bulb of any given Tigridia will be identical with
the parent form.

A certain amount of diversity there must
always be, because no two living organisms are
absolutely identical.

But for all practical purposes it may be said
that the different plants grown from offshoots of
an original bulb are identical. The process of bulb
division can be repeated a thousand or a million
times, until the original bulb has been so multi-
plied that its descendants people the earth. But
from first to last, one bulb will be substantially
like another, and all the myriads of plants that
have thus arisen may be said to constitute a single
personality.

All this is such familiar matter of fact as to
excite no comment.

Yet, rightly considered, it is a fact of the most
mystifying kind and one that must excite wonder-
ment on the part of anyone who gives it serious
consideration.

[95]

LUTHER BURBANK

That the multitudes of hereditary factors that
exist in the germ plasm of so complex an organism
as a flowering plant should be grouped in each
successive bulb that develops as an offshoot of the
original bulb of that plant in precisely the same
combination, pre-determining the production of a
future plant identical with the original, is a fact
that becomes increasingly mysterious the more
carefully we consider it.

In particular, the mystery is great if we have
kept in touch with modern ideas as to the segrega-
tion of the germ plasm and the body plasm of the
living organism. There is a current notion, sup-
ported by high scientific authority, that the very
earliest division of a fertilized egg cell, in the case
of an animal or plant, results in the separation of
the infinitesimal fleck of protoplasm into two dif-
ferent parts tha't are fundamentally different, one
carrying the body plasm from which the structure
of the new individual is to grow, and the other
carrying the germ plasm that is to convey the
potentialities of future offspring.

New studies in the biological laboratory have
shown that this idea, that the first division of the
egg cell results in such a segregation of body
plasm and germ plasm, cannot be fully accepted.
Nevertheless it is obvious that in the case of all
higher organisms, whether vegetable or animal,

[96]

A Blue Tigridia

Here is a Burbank hybrid tigridia that has taken on a

color variation that is very striking. It is a complex hybrid,

further developed by careful selection in Mr. Burbank's garden.

represents the result of one of his most interesting series

of experiments in breeding the tigridias.

It

LUTHER BURBANK

the germ plasm may be a thing apart. As finally
segregated, for example, in the ovules and pollen
grains, it constitutes a concentrated aggregate that
transmits the hereditary factors from generation
to generation in a sense independently of the
bodily characteristics of the individual plant.

You may, for example, determine that a given
flower and the seed that grows from it shall be of
exceptional size and vigor by cutting off all other
flowers so that the energy of the plant shall be
concentrated on a single one. But in so doing you
merely give added vigor to the new generation;
you do not alter its fundamental hereditary char-
acters. These are pre-determined by the factors
in the germ plasm that have been brought from
earlier generations and of which the individual
plant is only the carrier.

All this, then, suggests the isolation of the germ
plasm; and the newest theories of heredity have
tended to emphasize the idea that germ plasm
and body plasm are things of a somewhat different
order.

Yet the phenomena of reproduction by root
division or by the putting out of new bulbs, fur-
nish a striking demonstration that the germ plasm
which predetermines the form of the future plant
is present not alone in the pollen grain and the
ovule, but also in the bulb.

[98]

ON THE TIGRIDIA

Even from the single bud of a bulb, as we have
seen illustrated in several cases, a new plant will
grow that will duplicate absolutely — in the inter-
pretation just given — the qualities of the parent
plant. And when we were studying the fruit trees
we saw that the same thing is true of any aerial
bulb if grown even on a foreign branch.

Root bulb and aerial bulb alike contain the

essential germ plasm of the individual of which

they are a part. They nurture potentialities of a

new individual that will duplicate the parent form.

GERM PLASM AND BODY PLASM

From all of which it follows that the germ
plasm of the plant cannot be thought of as isolated
from the body plasm. It may well enough be
segregated within the substances of any given cell.
But that it is present in connection with the living
cells of the plant everywhere, from its roots to its
remotest stem, is clearly demonstrated by the
every-day methods of propagation employed in
orchard and garden.

Such being the case, it is difficult to avoid the
conviction that the germ plasm that is part and
parcel of every cell of the body plasm of the entire
plant is more or less subject to the environing
influences that effect the body of the plant. And
from this it would follow, at least as a reasonable
inference, that environing influences that modify

[99]

ON THE TIGRIDIA

the structure of the plant body must have an effect
in modifying also the germ plasm in a way to
influence the character of the future plant that
develops from that germ plasm.

And as much as this, it should be added, is
admitted by all experimenters, even by those who
deny the possibility of the transmission of acquired
traits in the older interpretation of that phrase.
That altered conditions of nutrition may modify
the condition of the germ plasm in such a way as
to modify the state of the offspring has been shown
by experiments in many fields, both with animals
and vegetables. Such being the case, the question
of the transmissibility of acquired traits is reduced,
as I have elsewhere quoted an authority as saying,
to a matter of definition.

Nevertheless, for practical purposes, it is
unquestionably true that the germ plasm is enor-
mously difficult to influence, and that under all
ordinary circumstances it will convey its heredi-
tary factors unchanged, or not appreciably
changed, from one generation to another. In
attempting to modify the forms of successive
generations, the method that has hitherto proved
successful, has been, not the modification of the
individual germ plasm, but the bringing together
of different germ plasms trom diverse organisms
through hybridization.

[101]

LUTHER BURBANK

For such union of germ plasms there is
obviously no opportunity in the case of the new
plant grown from the bulb.

Hence the fixity of type of plants propagated in
this way — a fixity that is often of the utmost prac-
tical importance, as in the propagation of a new
race of vegetables or flowers, but which, by the
same token, puts the plant thus propagated outside
the field of the plant experimenter.

COMPLEMENTARY MODES OF PROPAGATION

Thus the two methods of propagation that are
available for such a plant as the tigridia and for
countless others of its ilk, are in a sense antago-
nistic or complementary in their influence on the
history of the plant itself.

Propagation by bulbs insures spread of the
race, but insures also maintenance of the racial
fixity.

Should environing conditions change, it is
unlikely that plants thus propagated could change
rapidly enough to adapt themselves to these
conditions.

But at the same time that the plant is producing
new bulbs it may also, year by year, produce seeds
that are the result of cross-fertilization. And this
method of propagation is a perpetual bid for such
variation as will make possible a relatively rapid
change in adaptation to a changing environment.

[102]

A Nameless Missionary Flower

This odd flower was grown from seeds sent Mr. Burbank
by a missionary from China. Many interesting results have
been obtained at Santa Rosa by experimenting with flowers sent by
missionaries. In this case, the similarity to the tigridias sug-
gests the possibility of hybridizing experiments, which,
however, have not as yet been undertaken.

LUTHER BURBANK

That vast tribes of plants should have found it
necessary to adopt both methods of propagation
is in itself an evidence of the struggle for existence
that is the basis of natural selection.

In another way, also, the bulb perhaps evi-
dences the hardness of the struggle for existence,
particularly in tropical climates. Everyone knows
that vegetation is exceedingly luxuriant in the
tropics, and it is a matter of observation that the
habit of developing tubers and bulbs is especially
common among the herbaceous plants of tropical
and sub-tropical regions. Perhaps one explana-
tion is that the storing of food-supplies in the bulb
enables the young plants to shoot up rapidly
without waiting for the development of a large
root system.

By so doing they may stand a chance of com-
peting with the surrounding vegetation and thus
have a far better chance of reaching maturity than
if they had grown from tiny seeds.

It is probable, therefore, that the generality of
bulbous plants that one would find in any given
locality in their native haunts would have devel-
oped as offshoots of the bulb of an original plant
or as inbred or close-bred. So the bulb has very
fundamental importance in the plant economy.
And it is interesting to reflect that it is correspond-
ingly important from a human standpoint, inas-

[104]

ON THE TIGRIDIA

much as bulbs furnish us some of our most
important food products.

We have seen that a good many of the plants
that are propagated solely from the bulb or tuber,
of which the potato is the most familiar example,
may give up the habit of seed production alto-
gether under cultivation. But, on the other hand,
it is observed that plants that produce compara-
tively small bulbs in the state of nature may be
stimulated to the production of far larger bulbs
and more abundant offshoots under cultivation.
And the inherent reason for this is obvious when
we consider the share the bulb must play in per-
petuating a species and aiding it in the struggle
for existence under widely varying conditions and
in competition with other plants.

Making application to the particular case of
the tigridia, it has already been recorded that I
have found no difficulty in doubling or even quad-
rupling the bulk of the bulb of that plant, as well
as greatly increasing the tendency to the multipli-
cation of bulbs.

I repeat that it will probably be found desirable
to cultivate the plant further along these lines
until it finds recognized place in the vegetable
garden as the producer of a food of the finest
quality, while at the same time retaining value as
the bearer of beautiful flowers.

[105]

1 1

1

FOUR

COMMON DOORYARD FLOWERS AND
THEIR IMPROVEMENT

WORK ON THE VERBENA, THE PINK, THE PETUNIA,
AND THE GERANIUM

MY most interesting verbena was the one
named the Mayflower. I use the past
tense because I am not sure that any rep-
resentative of the variety named Mayflower is now
in existence. I have introduced the plant through
a prominent horticulturist, but he apparently
found it difficult to reproduce it with sufficient
rapidity from cuttings and so attempted to
propagate it more rapidly from seed.

Unfortunately the verbenas are so mixed a
tribe, and the various races so little fixed, that
they do not breed true from the seed. And so
when I myself sent to the horticulturist for a
sample of the fragrant Mayflower verbena a few
years later, I received a plant that had but a
reminiscence of the distinguishing quality of the
original.

In the meantime, however, I had developed

[VOLUME X — CHAPTER IV]

LUTHER BURBANK

another race of fragrant verbenas, which was
introduced in 1901 under the name of Elegance
verbena. These are the two stocks from which a
large number, at any rate, of the fragrant verbenas
now under cultivation have been developed.

My first fragrant verbena, the Mayflower, was
developed after I had worked for many years with
this flower and had grown great quantities of the
seed for distribution. The plant from which the
fragrant race was developed was found among
many thousands, most of which, as is usual with
the cultivated varieties, have a rather disagreeable
odor.

I had noticed, however, that there were mem-
bers of the verbena colony that had a very slight
fragrance, especially in the evening. So I began a
careful search among them to find a plant the
flowers of which had the most pronounced per-
fume.

After a long search among the thousands, I
found at last a plant that was distinctly fragrant,
markedly surpassing in this regard any of its
associates.

This individual was of course carefully isolated
and its seeds were gathered. In due course I had
a number of seedlings among which some were
found that produced flowers more fragrant
than those of the parent. The selection was con-

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tinued, according to my usual method, through
successive generations, until at last a plant was
found that is as fragrant as could be wished. The
plant in question was an exceedingly large ver-
bena— in fact one of the largest ever grown. The
flowers it bore were of a rich rosy pink in color,
the exact counterpart of the color of the familiar
trailing arbutus or any flower of New England.

Curiously enough the fragrance of the new
verbena was also precisely that of the arbutus in
quality, although it was much more intense, as
was readily admitted by all who tested the two
flowers side by side.

It was for this reason that the new verbena
was given the name of Mayflower.

Several perfumers who saw this verbena were
agreed that it would be of value for the produc-
tion of a perfume. It was admitted by all that no
verbena with a comparable odor had ever before
been seen.

The subsequent history of the Mayflower has
already been told. It was purchased by a dealer,
and although plants grown from cuttings made
from it are probably in existence, I do not know
where they are and do not know how to trace
them.

Aside from its fragrance, the Mayflower was
an interesting type of verbena, owing to its size

[110]

ON FOUR DOORYARD FLOWERS

and prolific bearing and the beauty of its flower.
But seedlings grown from the plant could not be
depended upon to produce flowers that would
reproduce the Mayflower odor. Indeed they could
not be depended on to reproduce any particular
characteristic of the parent plant.

In point of fact, seedlings of the Mayflower pro-
duced plants bearing blossoms of almost every
color — scarlet, crimson, almost pure white, yellow,
deep cobalt blue, purplish. But not one of the
many thousands I raised afterwards had the
delightful flavor of the Mayflower.

THE MAYFLOWER ACCOUNTED FOR

As might be inferred from its variability, the
fragrant verbena was a very mixed hybrid. It
was the outcome of hybridizing experiments in
which I had utilized the various races of the plant
under cultivation. I had not only grown and
crossed the ones that are in the seed catalogs, but
also secured seeds from all four of the original
species from which the cultivated verbenas have
been developed, collected from wild plants in
South America.

It is quite unnecessary, however, to hybridize
the verbenas in order to secure variation, as all
of those that are under cultivation are themselves
hybrids of very mixed strain, and the plant has
been cultivated for a comparatively short period

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and none of the familiar forms breed true from
the seed.

The ancestors of the cultivated verbena were
South American plants, and it is believed that
there are four chief species that have been vari-
ously hybridized to produce all the forms now
under cultivation. One of these bears flowers of
brilliant red, two others have flowers that are rosy
or purple in color, and the flowers of the fourth
are pure white.

The hybridized races show the breaking up of
these colors, quite as might be expected, with the
presentation of all the primary colors in many of
their hues and gradations, although pure blues are
not well represented, and pure yellow is very
exceptional.

But the point of greatest interest in the present
connection is the fact that the white species of
wild verbena, which is acknowledged to be one of
the forms, whose strains have been blended with
the others to produce the cultivated verbena, has
what is described as a rich jessamine fragrance.

The hybridizing experiments that ultimately
gave us the perfected verbena were carried out
less than a century ago, but in the meantime the
strains have been so mixed and blended that it
would be impossible for the most part to trace the
characteristics of any given form of cultivated ver-

[113]

LUTHER BURBANK

bena with certainty. But it is obvious that the
hybridizers and those who further developed the
plant by selection were chiefly influenced by form
and color, as has been the case with so many other
flowers, and paid little attention to the question
of fragrance.

The verbena has been made to develop won-
derfully symmetrical clusters, and its flowers have
taken on the most gaudy hues. But in the main,
as already pointed out, the odor even of the most
beautiful specimens is disagreeable rather than
attractive.

Yet one of the wild parents, as we have just
noted, was fragrant; and our previous studies of
heredity give us full assurance that the factors for
fragrance must be retained in some at least of the
hybrid progeny, and will now and again make
themselves manifest. That such is really the case,
my fragrant verbena clearly enough demonstrates.
To be sure its fragrance is not just that of the
original. Some slight chemical modifications have
taken place, doubtless through the blending of
other chemicals that represent the odoriferous
qualities of the other species, and it is only by rare
exception that an individual appears having just
the right combination to produce an attractive
perfume.

But the point of interest is that when such an

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individual does appear, as in the case of the May-
flower and the later form named the Elegance,
the anomaly is accounted for quite adequately by
a knowledge of the existence of fragrant species
among the ancestors of the hybrid.

Even if we had no knowledge of the existence
of such an ancestor, we should still be justified in
assuming that a fragrant verbena is really a case
of atavism. It will be recalled that we invoked
the existence of remote unknown fragrant ances-
tors in explanation of the appearance of our fra-
grant calla. But there is an element of added in-
terest in the knowledge that in the case of the
verbena the ancestor responsible for the quality
of fragrance can be traced.

It would constitute a very interesting experi-
ment in heredity, should someone care to under-
take to hybridize a fragrant verbena with an odor-
less one and to trace carefully the hereditary influ-
ence of this quality — noting, for example, whether
it acts as a prepotent or as a recessive character,
and whether it tends to reappear in the second gen-
eration in any fixed proportion of the progeny.

It will probably be found that the condition
that leads to the production of perfume of a par-
ticular type is so complex and itself dependent
upon so many factors that it is not inherited in
any simple and readily traceable relation.

[116]

ON FOUR DOORYARD FLOWERS

One of the distant relatives of the fragrant ver-
bena is a fine shrub, worthy of introduction, known
as the Alovsia citriodora. Another, as different as
possible in appearance, is a little trailing plant
known as Lippia repens.

This little trailing plant is very valuable as a
substitute for lawn grass. It requires less than
one tenth the water required by blue grass, and
only a fraction of the care. It need be sown only
once or twice in a season, and throughout the sum-
mer it will cover the lawn with a dense foliage,
and bear a mass of small blossoms resembling
those of white clover and fully as attractive to the
bees.

Unfortunately the lippia is not very hardy, and
when the temperature goes much below freezing
it turns to a disagreeable brownish color. Thus it
is not adapted to the cold climates of the Northern
United States.

If it could be given hardiness through selection
and cultivation, it would prove a very important
acquisition for the making of lawns that will with-
stand the summer drought.

An allied species is the moss-like Verbena eri-
moides, which is an exceedingly pretty plant grow-
ing wild in the high Chilean mountains. In Cali-
fornia it produces seed so abundantly and hence
multiplies so rapidly that it becomes almost a

[117]

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ON FOUR DOORYARD FLOWERS

weed. It is possible that new and interesting vari-
eties of verbena may be produced by hybridizing
the familiar cultivated ones with some of the wild
species that have not hitherto been brought into
the combination.

CARNATIONS, OR PINKS

It is rather anomalous that a plant should bear
at the same time two popular names suggestive of
colors so different as pink and carnation and the
anomaly is not lessened by the fact that the plant
itself bears flowers not only of the colors suggested
but also of the purest white. Such, however, is the
case with the plants that are known to the botanist
as constituting the genus Dianthus.

Despite the paradox, however, the Dianthus
fully justifies its popular names, for specimens are
of the most vivid carnation and others are of the
most beautiful pink. Meantime the white ones
are as beautiful in their way as either of their
more gaudy sisters.

Our studies of other flowers have made it seem
commonplace enough that a plant should show
such diversity. But the carnation as represented by
one of my hybrid varieties, presents a color anom-
aly that has not been shown by any other flower
with which we have made acquaintance; nor,
indeed, so far as I am aware, by any other flower
whatever.

[119]

LUTHER BURBANK

The anomalous plant in question is one that
produces flowers that are snow white in the morn-
ing when they first open, yet which at noon are
bright pink, and which, finally, toward evening
assume a deep crimson color. Each flower goes
through this process during the first day, but some-
times the changes in color take place a little more
gradually; so that each morning one may see on
the same plant carnations that are crimson, a few
that are pink, and freshly opened ones of white,
giving the plant a very striking and unique
appearance.

It chances that the plant that bears this curious
flower is a most astonishing bloomer, seeming
indeed to have more blossoms than foliage. So its
tri-color display is indeed a striking one.

The plant that bears these anomalous flowers
is the hybrid offspring of a white carnation and of
the deep crimson one known as Dianthas
Chinensis.

The plant itself is about eight or ten inches
high and of quite compact growth, in these regards
pretty closely resembling the Chinese parent. The
foliage appears to be about an even combination
of the characters of the parents. The flowers, as
we have seen, combine the traits of the blossoms
of the parent forms in a very anomalous way. Our
earlier studies would lead us to expect that the

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combination of a crimson flower with a white one
might produce crimson or white or pink. It would
not surprise us to find hybrid plants of the same
fraternity some of which bore the crimson flowers
of one parent, others the white flowers of the
other parent, and yet others pink flowers repre-
senting a blending of the two colors.

This indeed would be perhaps what we would
expect of such hybrids, if not in the first generation
then in the succeeding generations. But that the
color factors should be so blended that each in turn
should be dominant in the same individual flower,
the transition from one to the other being marked
by the appearance of an intermediate color, is an
anomaly for which our studies of color hereditary
have supplied no analogy.

We have considered it strange enough that
different colors should be arranged in stripes on a
flower as in the case of the four o'clock or in the
new hybrid tiger flowers. But the carnation that is
white at first and then pink and then crimson
seems to suggest an even more curious compro-
mise among conflicting hereditary factors. It
evidences anew the curious flexibility of color
schemes as applied to the petals of flowers, and
presents the evidence from an altogether new
angle.

It may be of interest to recall, in connection

[122]

ON FOUR DOORYARD FLOWERS

with this curious manifestation of color heredity,
that the carnation has been under cultivation from
an early historical period. The name Dianthus,
signifying divine power, is said to have been given
it by Theoprastus three hundred years before
Christ.

The flesh color of the original carnation was
broken up into red and white more than three
centuries ago. Since then multitudes of varieties
have been developed. Yet there is a strong pro-
pensity in this flower to hold to uniformity of color
as regards any individual flower. That is to say,
carnations in general are likely to be uniformly
scarlet or uniformly pink or uniformly white.
There are variegated forms, to be sure, but these
are exceptional.

This tendency of the flower to hold to one color
or another may at least be recalled with interest in
connection with the curious propensity of the tri-
colored hybrid to give recognition to the different
colors of its parents in the same flower in
successive periods of time.

But however the anomaly may be explained,
the tri-colored carnation was an interesting flower,
whether considered from the standpoint of the
horticulturist or from that of a student of
hereditary.

I have produced no other variant of corre-

[123]

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ON FOUR DOORYARD FLOWERS

spending interest in this tribe, although I have had
twenty-five or thirty species of Dianthus growing
for the purpose of crossing, and have produced
some other variants of minor importance.

In general, it may be said that the carnation,
having been worked on by plant experimenters for
two thousand years or more, presents a difficult
problem for anyone who strives to develop new
races of unusual value. It is like working against
the traditions of the ages to attempt to modify the
characteristics of such a plant in a new direction.
THE PETUNIA

The experiment in which I hybridized the
petunia with the tobacco plant, producing the
amonaly that was described facetiously as "the
petunia with the tobacco habit," will be recalled
as having been described in an earlier chapter.

Doubtless this experiment constituted my most
interesting work with the petunia, although I have
cultivated it largely and have attempted to cross
it with other species, notably with the allied plant
known as Salpiglosis. This plant is regarded by
botanists as very close to the petunia, but I have
been unable to effect a cross hybridization.

It will be recalled, however, that I hybridized
the petunia and the tobacco with difficulty, and
it is possible that a more extended series of experi-
ments might result in hybridizing more satisfac-

[125]

LUTHER BURBANK

torily with Salpiglosis, for the plants are botani-
cally related pretty closely.

An illustration of what can be accomplished by
an amateur who devotes attention to a single plant
is given by the work of Mrs. Sheppard, of Ventura,
California, and her neighbor, Mrs. Gould. The
former took up the cultivation of flowers for the
healthful outdoor life on the recommendation of
her physician, and the latter became interested in
the work through observation of the results
achieved by her neighbor.

On the advice of Mrs. Sheppard, Mrs. Gould
took up the cultivation of the petunia as a spe-
cialty. The result has been that some of the finest
strains of petunias that are known have been sent
out from California. One of the largest and best
of these is the form known as the Ruffled Giant.

A great amount of time and skill are required
in raising the best petunia seed, and there is still
opportunity for improvement. It is particularly
necessary to use good taste in the selection and
combination of the colors. It is found to be, on
the whole, easier to produce large flowers than
those having a blending of clear, pleasing colors.
There are a few common garden plants that give
better opportunity for work of the amateur, par-
ticularly for one who has gained a certain amount
of skill through previous experiment. The inter-

[126]

LUTHER BURBANK

esting character of the petunia tobacco hybrid will
be recalled. Doubtless by sufficient persistency
other hybrids having equal or even greater interest
could be produced.

GERANIUM AND PELARGONIUM

Several years ago I brought all the geraniums
that I could obtain from European and American
florists and collected also some fine specimens of
a variety from British America. The last named
variety is exceedingly hardy, growing as far north
as Alberta, where the thermometer sometimes falls
60 degrees below zero in winter. I thought it would
be of interest to hybridize such wild species as this
with the cultivated varieties.

The pressure of other work, however, prevented
me from carrying out the experiments on an ex-
pansive scale. I feel, however, that the experiment
of crossing the wild and cultivated geraniums is
well worth undertaking. The wild geranium is a
much more promising plant to work upon, in my
opinion, than was the original violet from which
all our beautiful pansies have been developed.
Indeed, there are few other plants among our wild-
lings that offer better opportunities for develop-
ment

My more recent work with the geraniums has
had to do more especially with the form known as
the Pelargonium, a plant that is horticulturally dis-

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tinguished from the geraniums, but which is obvi-
ously closely related.

An interesting story is told of the way in which
the Pelargonium was introduced into cultivation.
A physician, experiencing difficulty in obtaining
plants from foreign countries and knowing that
the seeds of many choice varieties often lie dor-
mant in the soil, commissioned a sailor to bring
him a barrel of soil from the Far East — I believe
from Borneo.

When the soil was received and spread out and
cultivated, numerous plants sprang from it, among
others the one that became the parent of the now
greatly prized race of Pelargoniums.

Whatever the truth of this anecdote, it at least
illustrates a possible way of securing new plants
from foreign countries. And however the Pelar-
gonium was introduced, it has proved a plant
worthy of the fullest recognition. It has, indeed,
obtained such popularity that the old-fashioned
types of geraniums have in many places lost their
vogue.

Hybridizing the geraniums is not at all difficult
when one understands the process. It is only nec-
essary to understand that the stigma of any given
flower does not mature until after the pollen of
the same flower has been scattered. Bearing this
in mind nothing more is necessary than to gather

[130]

ON FOUR DOORYARD FLOWERS

pollen and dust it on the stigmas of plants that
have already shed their pollen. To make abso-
lutely sure about guarding against the self-fertili-
zation of the flower, it would of course be neces-
sary to remove the stamens before ripening.

Some of my experiments in hybridizing have
been conducted with the idea of producing fra-
grant races of geraniums. The chief difficulty in
this work is that most of the fragrant geraniums
have been grown for such a length of time from
cuttings that they have for the most part lost the
power of producing seeds. This makes it obvi-
ously difficult to secure seeds from the plants that
are precisely the ones it would be desirable to use
for the purpose.

Nevertheless I have produced a number of vari-
eties having fragrance of very attractive quality.

One of these fragrant varieties is developed
from a compact growing Australian form which
produces an enormous amount of seed. If this
form were crossed with the other fragrant varie-
ties a valuable type should be produced, as this
plant has recently come from the wild and would
instill vigor into the specialized and long cultivated
plants.

A line of work that I carried out at one time
involved the crossing of the Pelargoniums with
variegated leaves with those having ordinary green

[131]

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ON FOUR DOORYARD FLOWERS

leaves. Among these crossbreds it appeared that
the green colored foliage was prepotent or dom-
inant over the white and yellow variations. The
horseshoe variations were more readily transmit-
ted, but there was a varying proportion of marked
and plain leaves among the hybrids.

I also worked at one time in selecting the gera-
niums for the production of large flowers of daz-
zling brilliant scarlet color, and with a good meas-
ure of success. One of the varieties thus produced
has been greatly admired by all who have seen it,
and will probably be thought worthy of introduc-
tion.

It will thus appear that there is abundant op-
portunity for improving the geraniums even by
working with the species ordinarily under culti-
vation. I repeat, however, that the best oppor-
tunity for work in this line will involve hybridizing
experiments in which the exceedingly hardy wild
species are utilized. It should be possible thus to
produce new races of geraniums that have alto-
gether exceptional quality.

The wild species include some that are white
in color as well as those that are pink or white
striped with pink or with reddish veins. So there
is opportunity to have a wide choice as to color
variation. The cross might likely result also in
giving the geraniums enhanced vigor so that new

[133]

LUTHER BURBANK

races of perpetual bloomers comparable to the
best of pelargoniums would be produced. Few
plants among all the popular favorites have greater
merits than the geraniums, and none, perhaps,
offer better opportunities for interesting experi-
ments that may be made by the amateur.

— A plant which has been
worked on by experimenters
for two thousand years pre-
sents a difficult problem for
anyone who strives to develop
new races of unusual value. It
is like working against the
traditions of the ages to
attempt to modify the
characteristics of such a
plant in a new direction.

THE EVERLASTING FLOWER

AND
SOME COMMON EXOTICS

THE AUSTRALIAN STAR-FLOWER AND PLANTS FROM
ORIENT AND TROPICS

NOT long ago I received a tentative order for
ten million clustered flowers in a single lot.
The order came from a French mil-
liner, who stated that unless he could get at least
ten million blossoms he could not afford to handle
them at all. I was too busy with other things to
attempt to fill the order, but the fact that it was
given is worthy of record as illustrating the more
or less unexpected opportunities that open up
before the plant experimenter.

The flowers that the French milliner wished to
use in such quantity are species of Composites
known commonly as Everlastings. These flowers
have long been popular because they retain their
form and color more or less clearly when dried,
and thus make permanent bouquets. In recent
years, however, the abundance of fresh cut flow-
ers has caused the everlastings to be much less
popular than they formerly were.

[VOLUME X — CHAPTER V]

LUTHER BURBANK

Now, however, it appears that a process has
been perfected through which, by chemical treat-
ment, the dried everlasting flowers are given a
degree of permanency and toughness of fiber that
makes them suitable for use in trimming hats.
Moreover, the grace and beauty of the new Austra-
lian star-flower are qualities not possessed by any
other everlasting. Hence the milliner's desire to
secure them in quantity.

Although I could not undertake to meet so com-
prehensive a request, I have nevertheless been ex-
perimenting for a number of years with various
tribes of everlastings. These are plants that orig-
inally came from the Cape of Good Hope, and are
hence known commonly as the Cape everlasting.
There is an Australian star-flower that is pretty
closely related, which is also an everlasting, and
it is with this that my chief work has been done.
This was sent me by my collector in West Aus-
tralia, who first discovered it.

With the more familiar tribes of everlastings I
have been well acquainted since boyhood, but it is
only in recent years that I have given them serious
attention. They are of many colors — red, pink,
crimson, yellow, orange, and white. Some of them
that are annuals in the eastern states became per-
ennials in California, even growing throughout the
winter. The everlastings with which I have ex-

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perimented most extensively belong to the genus
Helipterum, and are known to the horticulturist as
Rodanthes. My work commenced with a so-called
double Rodanthes, which varies from white to red
in color.

The seeds that furnished the original stock were
said to represent a double flower, but only a small
proportion of the plants that grew from them bore
flowers that were really double. That is to say,
there was almost invariably a center devoid of
petals. My work consisted in selecting to fill up
the center, and make a flower that is altogether
double.

The flowers vary much in size, and the colors
are so variant as to supply good material for selec-
tion. But a difficulty arises in that the plants pro-
duce very little seed. My selective experiments
have now extended over a number of years, and I
have been able to increase the size of the flower,
to improve it considerably hi the matter of double-
ness, and to isolate to a certain extent the different
colors, although the plant as yet is not fixed in any
of these regards sufficiently to justify its introduc-
tion. The improvement already shown, however,
justifies the expectation that varieties of this ever-
lastings could be developed that would show
marked improvement over old types.

I am experimenting also with everlasting flow-

[138]

ON SOME INTERESTING ALIENS

ers of various other genera, including a Gono-
hrena, the seed of which was received from South
America. This plant has been under cultivation
for many years. It is a low growing plant, having
globular, crimson flowers. The introduction of
new blood from the wild South American repre-
sentative may be expected to have the usual stim-
ulative effect, increasing the vitality of the plant,
and perhaps urging it to greater variation.

The Australian star-flower first mentioned in
this chapter most resembles Rhodanthea, but is as
distinct as a rose is from a carnation. The bot-
anists have not been able to decide as to its specific
name. With the exception of the Rhodanthea, this
is without doubt the most beautiful of all the flow-
ers called everlastings so far discovered or pro-
duced. The beautiful star-shaped, rosy-crimson
and white clusters of flowers, produced in the
greatest abundance, are surpassingly beautiful.

The plant is an annual, produced only from
seed. The reason that this flower has not been
more generally grown all over the world is that it
is peculiarly subject to the attacks of soil fungi.
On virgin soil it always thrives; on cultivated soil,
sometimes. There is no doubt that this most beau-
tiful of everlastings can finally become immune
to fungi in cultivated soil through selection.

My work with the Australian star-flower has

[139]

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ON SOME INTERESTING ALIENS

consisted of increasing the size of the blossom,
making it semi-double, giving it added brilliancy
of color, and to some extent rendering it resistant
to disease. This has been accomplished by the
usual method of selection, strings being tied about
the better specimens, and finally the one best being
saved for seed. Very great improvement was
made, considering that this was a wild plant never
before under cultivation. The selected varieties
do not as yet breed true from the seed.
THE TRIBE OF CRINUMS

In an earlier chapter mention was made of
hybridizing experiments in which certain mem-
bers of the amaryllis tribe were crossed with cer-
tain of the Crinums. It is desirable to make addi-
tional reference to some experiments in which the
crinums themselves were variously developed and
hybridized with rather striking results. The hy-
brid Crinums are a really splended group of
bulbous flowering plants in which the bulbs are
in many cases of enormous size, and the leaves
are broad and long, making the plants very con-
spicuous.

Some of the leaves, indeed, are of gigantic size,
and the stalk that bears the flowers may grow to
a height of from four to six feet. The flowers
themselves are of variant color, from white to rosy
pink, and sometimes almost purple. They are

[141]

LUTHER BURBANK

borne in profusion, and their attractiveness is often
enhanced by their fragrance.

The crinums were originally residents of the
tropics, being indigenous to various parts of South
America, the southern United States. There are
several species that are hardy in California. In
some cases they will withstand freezing, so that
even if the leaves are destroyed by the frost the
new growth will put forth in the spring, and they
will bloom as abundantly as if they had been care-
fully housed over winter.

Like most other bulbous plants they thrive best
in sandy soil.

Some of the crinums are evergreen under ordi-
nary temperature, others are deciduous like most
of their relatives of the amaryllis tribe.

The chief objection to the crinums for house
culture is the enormous size of the bulb, and the
tendency to produce a superabundance of foliage
out of proportion to the number of flowers; al-
though this criticism does not apply to all of them.

Ten or twelve years ago I had probably twenty
species of crinums, some of them having been
brought from the tropics. My object was to com-
bine the good qualities of the tropical and sub-
tropical species with those of the hardy ones that
had become acclimated in California. No diffi-
culty was experienced in crossing the various spc-

[142]

A Burbank Crinum

The crinnm is an interesting member of the amaryllis

family, with which Mr. Burbank has performed a very large

number of interesting experiments. Unfortunately the crinumg are

not very hardy, else they would be much more popular

in our gardens than they are at present.

LUTHER BURBANK

cies, and hybridization was carried out in the usual
way, different pairs of species being mated and
then the hybrid forms in subsequent seasons re-
mated, noting of course at all stages which com-
binations seemed to produce the best results.
Mixed hybrids were finally produced that com-
bined the strains of many species.

The results were highly interesting.

In the course of a few years I had a strain of
crossbred crinums presenting most of the desir-
able qualities of the different species in combina-
tion. The new plants, in spite of the strains
of tropical species in their germ plasm, are very
hardy, withstanding the coldest weather of this
region without injury. They have very large flow-
ers, varying in color from white, pink, and rosy
crimson to purple. The petals are broad, and the
flowers in a large number of cases are fragrant.

The bulbs of some of these hybrids have taken
on extraordinary growth. At four years of age
some of them are from six to eight inches in diam-
eter, and twelve to eighteen inches in length,
weighing probably from ten to fifteen pounds, or
even more. More recently specimens have ap-
peared of even larger dimensions. Some of these
enormous bulbs seldom make offsets, others pro-
duce from one to twelve or more offsets in a sea-
son, so that they can be multiplied quite rapidly.

[144]

ON SOME INTERESTING ALIENS

The seedlings from these hybrids produce
plants that as a rule show a combination of two
or more of the species fairly well balanced. The
seed parent of the larger number of my hybrids is
the Crinum Americanum, but in some cases the
Crinum amabale, or the Crinum Asiaticum was
the seed parent. It is observed that a certain small
percentage of the hybrids show a strong propensity
to run toward the seed parent of whatever species.
This can generally be detected by the foliage when
the plants are quite small. I have not observed
that any of the hybrids depart so strongly the
other way toward the tropical species (the pollen
parent).

In the second and third generations the varia-
tions are better balanced through selection, and
become more fixed in desired qualities than at
first, when grown from seed.

On the whole, it is perhaps a little easier to get
new species of crinums by crossing and selection
than with most other bulbous plants, especially the
lilies — although there are notable exceptions
among the California lilies, some of which cross
very readily.

I have sold a number of the hybrid varieties of
crinum, but they have been introduced unnamed,
or at least were not named by me.

The crinum seeds are very curious, in that they

[145]

An Improved Burbank Crinum

This sturdy plant, with its beautiful lily-like

flowers, is an improved variety of crinum, developed by

selective breeding. It is a flower meriting a place in any garden.

ON SOME INTERESTING ALIENS

vary enormously in size, almost always in the
same capsule. The pale-greenish bulblike seeds
with irregular corrugations may vary from the
size of a pea to that of an English walnut. When
placed in a graded sequence they present a curi-
ous contrast. Yet the plants grown from the small-
est seeds are likely to be quite as large and of the
same appearance and quality as those grown from
the mammoth ones. The seeds of the crinum thus
furnish a unique link between seeds, buds, and
bulbs, suggesting the properties of all these
combined.

Another peculiarity of the seeds is that they
contain so much nutriment and moisture that they
may sprout and grow, making plants of consider-
able size, without access to any moisture except
that contained within the seed itself. I have
known them to sprout when laid on a shelf, or in
envelopes, away from the light and entirely dry;
also when sent to me by mail from Australia they
sometimes started as seeds and arrived here in
envelopes as small growing plants.

The crinums have been under cultivation for a
long time, and interesting hybridizing experiments
were made with them a century ago by the Rev.
W. Herbert, Dean of Manchester, whose experi-
ments with the gladiolus and other flowers have
been elsewhere referred to. But there are many

[147]

LUTHER BURBANK

species that have not been so largely experimented
with, and the opportunity to introduce new forms
from the tropics, together with the striking char-
acter of the plants themselves, gives them peculiar
attractiveness for the experimenter. The possibil-
ity of making still wider hybridizations, as in the
case of the cross with the amaryllis, and further
selections, should of course not be lost sight of.

THE SPECTACULAR IXIA

Another tribe of bulbous plants that have great
interest is that represented by the genus ixia.
These, like so many other of the interesting bul-
bous plants, are natives of the Gape of Good Hope,
and they are closely related to the gladiolus, and
resemble many other Cape bulbs, including the
Watsonias. There are various species, but they
have been so intercrossed and mixed that the ex-
perimenter need pay very little attention to specific
names and distinctions. The bulbs are inexpen-
sive, and are commonly grown several in a pot in
the house in winter in the eastern states, but in
California they grow outdoors, and there is no oc-
casion to transplant them, except for propagation.
A single bulb will spread by putting out new
bulbs, which in turn make offshoots in the same
way, until a large and beautiful clump of plants is
often developed. The ixia, indeed, can never be
seen at its best except when grown in this way.

[1481

Hybrid Crinum

Mr. Burbank has hybridized the crinum with the true

amaryllis, producing a plant with enormous bulbs and with

pleasing, if not particularly spectacular, flowers. Unfortunately the

hybrids do not bear seeds, although they blossom freely. So the

experiment has not been carried beyond the first generation.

LUTHER BURBANK

The flower stems are thrown up in great abun-
dance on long, stiff, wiry stalks, and the graceful
upright or drooping flowers are of every color
except blue — crimson, yellow, and white being the
characteristic colors.

The variety of ixia known as the Wonder has
double flowers that are exceptionally handsome.
The group of ixias make so striking an appearance
that they compete with the giant amaryllis in my
gardens in May for first place in their appeal to
the average visitor.

The two plants are utterly different, but each
in its way is most individual and striking; the ixia
being characterized by gracefulness and fragile
beauty, the other by its massiveness. The flowers
of the ixia are only about two inches in diameter;
those of the others eight to ten inches, yet the
massed effect of the ixia is so striking that it com-
petes in interest with the larger flower.

I have worked in a more or less desultory way
on the ixia for the past dozen or fifteen years. The
varieties under cultivation are so mixed as to their
ancestry, and hence have so strong an inherent
tendency to variation that it is not necessary to
cross them. Even the double variety is probably
at least half a century old. My work of improve-
ment looks to the increase in size and brilliancy
of color of the flower; and, of course, here as

[150]

ON SOME INTERESTING ALIENS

always, attention is paid to gracefulness and abun-
dance of blooming, and vigor and general health
of the plant.

The improvements in all these regards have
been quite striking, although I have not considered
any individual variety worthy of introduction
under a new name.

Notwithstanding the amount of work that has
been done with them, the ixias will well repay the
attention of the amateur who cares to work with
them.

ORIENTAL POPPIES

In an earlier chapter an account was given of
my blue poppy. An account has also been given
of the development of new colors in the flower
usually called the California poppy, but more
properly known by the somewhat forbidding name
of Eschscholzia. Very little has been said, how-
ever, about the experiments with the well known
annual and perennial poppies, which have pro-
duced some results of considerable interest.

The poppies in question are the opium poppy
(Papaver somnifera), and one previously called
the Oriental (Papaver orientalis) .

The opium poppy is, as everyone knows, a
commercial product of vast commercial impor-
tance in the Far East. It has been under cultivation
in Europe to a greater or less extent for several

[151]

Seed Pods of the Crinum

The seeds of the crinum show an extraordinary range of

variation, some of them being small, whereas others are so

large as to suggest miniature bulbs. The latter are so succulent that

sometimes they sprout when lying on the shelf. On one or two

occasions Mr. Burbank has had crinum seeds sent from a

distance by mail, which sprouted en route. This is

an interesting and very unusual peculiarity.

ON SOME INTERESTING ALIENS

centuries, and has been greatly improved by the
European growers, the varieties developed being of
almost every shade of color, some flowers being
single and others double.

From time to time charming varieties have been
sent out in recent years, including an interesting
single one known as the Miss Sherwood, a variety
having blossoms with a white center and crim-
son edge, the petals being beautifully fringed.

There are other varieties known as Paeonia
and Carnation Flower poppies that are double and
are exceedingly handsome in color.

The Oriental poppy has very large flowers,
always crimson with shadings of scarlet in color
in a state of nature, and in almost all cultivated
varieties — the color being unusually well fixed.
The plant is a perennial with rough, hairy leaves.
The flowers are borne on single stems, instead of
branching from a main stalk as in the opium and
most other poppies. The Oriental species has
probably not been under cultivation as long as the
other, but many varieties have been developed,
some of them semi-double, and the colors have
been modified so that there are dull white, scar-
let, and yellowish varieties, as well as the more
usual crimson.

These varieties, however, seem not to be well
fixed — they do not come true from the seed — and

[153]

LUTHER BURBANK

the best varieties so far produced quite generally
appear to be lacking in vitality — possibly from
overzealousness in selection by division, the only
way of maintaining and multiplying any special
variety.

My own experiments have largely had to do
with hybridizing the Oriental and the opium
poppies.

Rather curiously I found that the pollen of the
opium poppy was ineffective when used on the
Oriental, yet when a reciprocal cross was effected,
the pollen of the Oriental being used on the opium
poppy, seed was produced, and a great number of
hybrids were soon under observation.

In the hybrid colony, comprising more than
thirty thousand of these plants, there was as little
variation in color as is usual with the Oriental
poppy. None of the hybrids were double, but they
had several interesting qualities.

One striking peculiarity was that the hybrid
poppies produced in some cases enormous seed
capsules, five or six times as large as the ordinary
seed capsule of either parent species. Yet in other
plants the seed capsule would be smaller than that
of either parent. In still other cases twin capsules
are produced uniformly, and with a certain num-
ber there was produced a mere rudiment of a
capsule. But the most striking of all were the

[154]

Chinese Opium Poppies

This is a variety of the flower, from the seed heads of
which the familiar commercial drug, opium, is extracted. Mr.
Burbank has experimented extensively with this as with many other
species of poppies, though not, of course, with refer-
ence to its opium-producing qualities.

LUTHER BURBANK

numerous plants that produced not even an inti-
mation of a capsule, the flowering stem ending
abruptly like the end of a lead pencil.

All in all the hybrids showing this extraordi-
nary variation in the seed bearing capsule — rang-
ing from enormous enlargement of the capsule to
its entire obliteration — make a very wonderful
and interesting study in heredity.

It is of further interest to note that, although
these hybrids were raised from seed of an annual
poppy (hybridized, however, by a perennial), yet
without exception every member of the entire
company of thirty thousand is a perennial.

The flowers, themselves, vary greatly in size,
some of them being seven or even eight inches in
diameter, while the smallest are perhaps only four
or five inches. Some are beautifully crimped,
others have flat petals, there being the most strik-
ing variations in form.

Even the specimens that have unusually large,
plump seed capsules may produce no thoroughly
well developed seeds. In a gallon of the seed-
pods, from which one might expect perhaps two
quarts of plump seed, I usually obtain perhaps
from one hundred to three hundred or four hun-
dred grains, mostly of shrunken ill-shaped seeds.
Yet these shriveled seeds when sown produce good
plants. Even seeds that seem so abortive that it is

[156]

Another Specimen of the Chinese Opium Poppy

It is probable that the Chinese opium poppy represents

the result of careful selective breeding on the part of unknown

plant developers. But the development of its drug-bearing qualities

has not interfered with the beauty of the flower, as is

evident from a glance at the specimen here shown.

LUTHER BURBANK

incredible they should germinate, may produce
perfectly healthy seedlings.
STRIKING VARIATIONS IN THE SECOND GENERATION

The second generation poppies produced from
these seeds were among the most remarkable com-
panies of plants that I have ever seen. All who
saw them agreed that they were the most variable
lot of plants of a single fraternity that they had
ever observed.

The diversity was so great that it might be said
that there were no two plants among the thousands
that were even approximately identical. No two
could be found in which differences could not
readily be observed in the foliage.

Some of the peculiar forms of leaf were these :
(1) Long, smooth strap-shaped leaves sometimes
not more than half an inch wide and a foot or
more in length; sometimes smooth and sometimes
villous; dark green or light green. (2) Short and
stubby leaves, trifoliate, either villous or glaucous.

(3) Leaves resembling those of the Oriental poppy.

(4) Leaves like those of the opium poppy. (5)
Nondescript leaves, variously suggestive of the
leaves of primrose, cherry, dock, wormwood, dan-
delion, and scores of others.

It is interesting to note that the blossoms of
the second generation varied somewhat less than
the leaves, although much more diversified than

[158]

A Hybrid Poppy

Mr. Burbank's experiments in hybridizing the poppies
are of exceeding interest. Here is a specimen of a cross be-
tween the opium poppy and the oriental poppy. The anomalous re-
sults of this combination, of great interest to students
of heredity, are related in the text.

LUTHER BURBANK

the blossoms of the first generation. Some were
double and of various shades of the opium poppy.
The range of color included almost black, deep
crimson, purple, light crimson, salmon shades,
pink, white, and various combinations of these col-
ors. Yet on the whole the color variation was not
greater than that ordinarily found in the opium
poppy.

The second-generation plants seemed not to
have the vitality shown by those of the first gen-
eration. There were exceptions to this, however,
individual plants manifesting a vitality in excess
of the average of the first-generation plants.

Most of the second-generation hybrids that pro-
duced double blossoms proved to be annuals or
biennials, partaking thus of the characteristic of
the parent from which they derived their double-
ness of blossom. This is perhaps what might have
been expected. It is notable, however, that the
quality of annual or biennial growth should have
reappeared in these hybrids of the second genera-
tion, the first generation hybrids having been, as
already noted, all perennials.

But, on the other hand, some of the second
generation hybrids were perennials, and have con-
tinued to live and thrive, bearing large quantities
of blossoms each season.

Thus the perennial and annual habit appeared,

[160]

Giant Oriental Poppy

The selected poppies sometimes attain very extraordinary

size. This blossom measured almost a foot across. Few flowers

afford greater interest for the amateur gardener than this spectacular

visitor from the orient.

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ON SOME INTERESTING ALIENS

in the case of these two poppies, to be a pair of
unit characters of which the perennial habit was
dominant and the annual habit recessive; there
being a characteristic segregation in the second
generation.

As to habit of blooming, there was another in-
teresting anomaly. The opium poppy, a strict
annual, blossoms only for a short period — for a
few weeks at most. The Oriental poppy, although
a perennial, also blooms but a short time. The
first generation hybrid poppies bloom persistently.
There is not a day in the year when some of these
hybrids are not in bloom, spring, summer, autumn,
or winter — blossoms can always be gathered in
quantity from them.

The hardiness of the hybrids has not been fully
tested. I should not be surprised to find that they
are largely as hardy as the Oriental poppy, but the
California climate does not subject them to a
severe test.

THE THIRD GENERATION HYBRIDS

In the third generation, a large number of the
hybrids reverted toward one or the other of the
original parents. But even those that resembled
one of the parents or the other strikingly, retained
also traits of the other parent. In this generation
the plants mostly produced no seed, and the tribe
partially ran out.

[163]

i

sla-5.^i?^E

ON SOME INTERESTING ALIENS

All these unique hybrids present such interest-
ing characteristics that it will be worth while to
record that the opium poppy that was used as the
original parent was of the Miss Sherwood variety,
but that later other opium poppies of every shade
and color that could be obtained were also used.
Perhaps in all twenty-five or thirty selected varie-
ties of opium poppies of various colors and differ-
ent forms were used as seed parents. The progeny,
however, as far as I could observe, varied little
and was not greatly influenced by the different
type of opium poppy used. However, the varia-
tion was so great in any event that it would be
difficult to judge as to this.

In general, the minor colorings and doublings
of color seemed to have less effect in the heredity
than the more fixed original foliage and flowers
of the wild plants. The hybrids show doubleness
and selected colors very slightly, except in a few
cases in the second generation, when there was a
tendency to return toward the original forms. It
should be noted also that the Oriental poppy, al-
though failing of fertilization when treated with
pollen of the opium poppy, produced seeds abun-
dantly when fertilized with its own pollen.

The size of the pollen and length of the pollen
tubes may conceivably have something to do with
the failure to effect hybridization when the Ori-

[165]

LUTHER BURBANK

ental poppy was used as the pistillate parent; but
this is only conjectural. Also, the opium poppy
has been so long under cultivation, and has become
so adaptable, that it perhaps is more pliable and
more ready to receive strange pollen.

The relative sterility of the first-generation
hybrids may be judged from the fact that almost
five thousand seedlings produced ten or twelve gal-
lons of capsules, but that there was only about a
quarter of a teaspoonful of seed to each gallon of
capsules.

As these seeds were shrunken and much
smaller than ordinary poppy seeds, however, the
actual number of seeds was proportionately large.
Still the total number was only a fraction of what
would have been the output of poppy plants of
normal fertility.

All in all, this experiment of hybridizing the
Oriental and the opium poppies, with the produc-
tion of relatively infertile hybrids showing Mende-
lian heredity as to some traits and a blending of
characters as to others, and a further segregation
and recombination of characters in the second
generation, constitutes an unusually interesting
experiment in heredity. I have made many other
experiments in breeding the various poppies, but
none perhaps that excelled this one in interest and
importance.

[166]

THE HYBRID LARKSPUR— AND
OTHER TRANSFORMATIONS

INTRODUCING A MISCELLANEOUS COMPANY

THE members of my larkspur colony are all
descended from a single individual.
That individual, in turn, was the select
and peerless member of a company of five thou-
sand, all of them of equally aristocratic lineage,
and each one of them worthy to show itself in any
larkspur company. But the usual rigorous method
of selection was applied to them.

The one individual that came nearest meeting
all expectations was preserved. The rest were
sent, with sundry thousands other plants of divers
species, to the bonfire.

The selected individual, of course, became the
progenitor of a new colony of larkspurs. Some of
these improved upon their ancestor, and among
them several interesting varieties were isolated
through selection.

The original parent form from which the one

[VOLUME X— CHAPTER VI]

LUTHER BURBANK

best larkspur was selected as the progenitor of new
races was of the species known as Delphinium
hybridum, or hybrid larkspur. As the name im-
plies, this plant is itself of hybrid origin, but it has
been cultivated a long time in Europe, being unus-
ually popular in England, and ranks as a true
species, or at least as a good horticultural variety.

There are numerous other species of larkspur,
sixty or more altogether. Some are annuals and
some perennials. Our native California species
are among the most beautiful. One of these,
named nudicaule, is a perennial growing along the
sides of streams and in shady canons, although
on occasion even mounting to the tops of high
rocks. It bears flowers of a bright orange red,
sometimes varying to yellowish, that are very
showy. The plant is easily cultivated either from
seed or by division, as indeed are all perennial
larkspurs.

Another species is D. cardinale, a large, strong
plant, growing in the southern part of California,
the flowers of which are also bright red and yellow
though quite different in general appearance from
those of the one just named. Yet another larkspur
that is of interest is the D. decorum, an extremely
variable form growing usually on overflowed land.

The flowers of this wild species vary almost as
much as do our hybridized and cultivated ones.

[168]

Improved Hybrid Larkspur

Few of Mr. Burbank's flower productions are more pop-

ular than his improved hybrid larkspur. This picture suggests

that the flowers amply justify their popularity. They are the product

of hybridization, as their name suggests, combined

with careful selective breeding.

LUTHER BURBANK

Growing side by side in a bed of wild larkspurs
of this species may be found plants bearing flowers
varying from deep blue, pale blue, dark rosy pink,
pale pink, and yellow, to almost pure white. The
flowers of these are quite large and showy, but the
colors, although so variant, are seldom brilliant

The larkspur known as D. Calif ornica is a giant
species, often found in canons toward the coast.
For a larkspur it towers to a great height, some-
times reaching seven or eight feet, but the flower
is insignificant when compared with most other
varieties both in size and color. They are purplish
blue or dingy white in color.

My attempts to cross this species with some of
our cultivated ones have not resulted in producing
anything of value.

Still another species is known as D. hespirium.
It grows in sandy or heavy black soil as the case
may be; is about two feet in height, and bears flow-
ers that are almost invariably of deepest blue,
although sometimes pink, pale blue, and white
ones are found.

These wild species are mentioned somewhat in
detail, chiefly to show the variation among them,
suggesting the possibility of interesting develop-
ments when the various forms are combined. I
have utilized them all more or less in experiments,
and in addition have grown nearly all the lark-

[170]

ON SOME FAMILIAR COMPOSITES

spurs that are ever offered by seedsmen or florists.
As already stated, my chief experiments began
with the use of the hybrid larkspur as a seed par-
ent, but of course the hybridizing experiments
soon blended the strains of many of the other spe-
cies, until the larkspur colony, like so many others
of flower groups, is of such conglomerate ancestry
that the precise proportions of the different strains
in any given race are not traceable.

Needless to say, selection has been carried for-
ward along with the hybridizing experiments,
these two methods always being complementary.
Particular attention has been given to size of
flower, vigor of plants, and resistance to insects
and disease, as well as that of multiplication by
division, at the same time that compactness of
growth and brilliancy of color of flower have been
carefully regarded.

One of the worst faults of the larkspur is that it
tends to grow too tall, with a stalk that does not
support it, so that it requires to be staked. But
my hybrid larkspurs have been so selected that
they are compact in growth, and able to support
themselves even in a moderate gale.

All the characteristic larkspur colors are rep-
resented among the new varieties, and in addition
there are combinations of color that have never
before been seen, I think, in the larkspur. Some

[171]

Color Variations in Hybrid Larkspurs

The hybrid larkspurs are very pleasing in form, and the

compact clusters in which they grow are peculiarly attractive.

But their other good qualities are enhanced by the wide range of color

variation, of which a suggestion is given in this picture. The

range of colors is striking, and all of the colors are pleasing.

ON SOME FAMILIAR COMPOSITES

of the individual flowers are considerably over
two inches in diameter, and some of the largest
are very double.

The color yellow is not usual with the larkspur,
its characteristic colors being red, blue, and white.
There is one yellow species, a native of southern
Asia. I have, however, developed varieties with
pale yellow flowers. The best of the selected varie-
ties, as descended from the original one chosen
among the first five thousand, is known as Bur-
bank's hybrid, and has been given full recognition
by seedsmen, florists, and gardeners. There is
still opportunity for further development among
the larkspurs, however, and improvements may be
expected which, if not spectacular, have at least a
fair measure of interest.

No plant is ever so fully developed that it does
not hold possibilities of improvement.
AN ALMOST ENDLESS VARIETY

The great family of composites presents an
almost endless variety of flowers, of which we have
seen some striking examples, most notable among
these being perhaps the daisies and the dahlias.
But now and again a new form makes bid for pop-
ularity, and there is still an indefinite amount of
material among our wild plants from which gar-
den plants might be developed.

Yet the old favorites are not necessarily sup-

[173]

LUTHER BURBANK

planted. Indeed there are some of them that have
perennial interest, holding their charm despite all
competition.

One of these is the marigold, of which there are
various species that find favor not only because
of the ease with which they may be cultivated, but
also because of the length of time during which
they bloom, the abundance of blossoms, and their
good keeping qualities after being picked.

The marigolds most commonly cultivated fall
into two distinct groups, one spoken of as the Afri-
can marigold and the other as the French mari-
gold. In addition to these there are native species,
among others a very interesting one that I have
received from Arizona, sent me by Professor
Lemon, whose name it bears. This native form is
a shrub about four feet in height, and in the fall
it bears a mass of beautiful single golden flowers
about the size of the French marigold.

This is one of the handsomest shrubs of this
sort, and although I think it has not yet been intro-
duced, it deserves a place in every garden, if — as
has not yet been proved — it will stand the colder
climate.

My experiments with the marigold were con-
ducted a good many years ago, chiefly along the
line of crossing the French and African races and
this new Arizona perennial species. In addition

[174]

A Brilliant Specimen

This is one of the most brilliant of the hybrid larkspurs.

It is a variety distinguished also by the large size of its flowers

and the wonderfully compact and symmetrical clusters. A flower

like this is a treasure in any garden.

LUTHER BURBANK

to their practical horticultural results, the experi-
ments gave some interesting illustrations of heredi-
tary influence,

In particular I observed that when the double
marigolds were crossed with the perennial single
species above mentioned all the hybrids were
single. Moreover, if I am not mistaken, they were
all annuals, though the perennial marigold was
the mother plant in every case.

It is interesting to recall that precisely the op-
posite result was produced in hybridizing the pop-
pies. In that case the union of an annual and a
perennial poppy produced hybrids all of which
were perennials.

One of the best marigolds with which I have
worked is called the lemonball. It is of the African
type, and it produces great lemon-yellow blossoms
in abundance, blooming throughout the entire sea-
son. The best specimens are thoroughly double,
but if the seed is saved from the most double blos-
soms, almost half of the seedling will bear single
flowers or those not perfectly double.

It is obvious that the factors for singleness and
doubleness tend to be segregated, and that the
strains of the double marigold have not all been
isolated in such a way as to produce germ plasm
that is unmixed as regards the factors for number
of petals.

[176]

A Distinctive Cluster

It is difficult to see how this hybrid larkspur could be

improved upon as to the symmetrical development of its flower

cluster, and the uniformity and excellence of its individual blossomst

nearly all of which, it will be seen, are in full bloom at the

same time. But in point of fact there are almost

numberless varieties of equal merit among

Mr. Burbank's hybrid larkspurs.

LUTHER BURBANK

Presumably this could be done by careful selec-
tion.

My more recent experiments have to do with
the general improvement of the marigolds, ana I
am also experimenting with a new species from
Chile with reference to its possible value as a pot-
herb for its fragrance and flavor. It is a tall, slen-
der shrub with innumerable pale, straw-yellow
flowers — almost white. Like one or two other spe-
cies of the genus it has a most delightful fragrance
and flavor. As regards quality and intensity of
flavor, it surpasses all others, but it apparently has
no other merit. Whether it will prove of sufficient
value for introduction in the vegetable garden is
still problematical.

A much less familiar member of the composite
family which, however, has gained rapidly in pop-
ularity in recent years is the plant known as cos-
mos. This is a Mexican species that is now making
its way into the flower gardens everywhere. It is
related to the plant known as the black dahlia
(Bidens astrosangiiinea) botanically, yet the rela-
tionship is not so close that the two can be com-
bined, at least I have not been able to effect
crossing between them.

A peculiarity of the cosmos, due doubtless to
its recent importation from a sub-tropical region,
is its habit of blooming very late in the autumn.

[178]

A Flower Cluster of Many Colors

Here is a bunch of hybrid larkspurs combining delicate
yellows, pinks, and blues. It would be an interesting experi-
ment to take the seeds of this single flower head, and endeavor to
produce, by selective breeding, varieties of larkspur having
flowers of uniform yellow and pink and blue re-
spectfully. Such possibilities as this are
open to any one who wishes to
experiment with this inter-
esting flower.

LUTHER BURBANK

This is sometimes regarded as a merit, but as the
plant is very tender, there is danger that its blos-
soms will be blighted by the early frosts. So the
most important work that has been done with the
plant in recent years is the production of early
blooming varieties. The effort has been so far suc-
cessful that there are now varieties that bloom in
midsummer. The fact that this modification has
been brought about within a comparatively few
plant generations illustrates the pliability of the
cosmos.

It is, in point of fact, one of the most variable
and pliable of plants — comparable in this regard
to the dahlia.

Such being the case, it is not surprising that it
has been found possible to develop new shades of
color, as well as much larger and finer flowers than
those of the original species. Forms with wider
petals, and others with twisted petals and other
variations of the corolla, have also been developed.
Even a double cosmos has been mentioned as
forthcoming. But the plant is comparatively new
in the flower garden, and it offers therefore rather
exceptional opportunities for the experimenter.

The amateur who is looking for a plant that
has not been carried to anything like its limits of
variation may advantageously pay attention to this
graceful, attractive, and rapid-growing composite.

[180]

ON SOME FAMILIAR COMPOSITES

The extreme heat and long days of the summer
even in high altitudes in the United States makes
possible the cultivation of a large number of flow-
ers that were originally of tropical habitat. Among
these no others are more familiar or have retained
their popularity more steadily than the tribe of
plants of the genus Iponoea, which numbers among
its representatives plants of such diversity as the
morning-glory, the moon-flower, the cypress vine,
the yam, and the sweet potato.

THE BRILLIANT MORNING GLORY

It is not difficult to account for the popularity
of the morning-glory. A vine that grows with the
greatest rapidity and that bears flowers of striking
and brilliant color in the greatest profusion, day
after day, for weeks together, covering our arbors
or pergolas in a few weeks' time, has merits that
are not duplicated exactly by those of any other
flower under cultivation.

The morning-glory has not been very exten-
sively worked with, but it has shown a marked
tendency to variation, and, as usual with plants
under cultivation, has broken up into numerous
varieties, showing in particular a wide range of
color variation. One of the most remarkable of
the varieties is the Japanese morning-glory, some
forms of which have double flowers of very curi-
ous structure. The single varieties of the Japanese

[181]

More Hybrid Larkspur Variations

Compare this cluster of hybrid larkspurs with those

shown in earlier pictures and in the succeeding one. After

making such a comparison, no one will need to be told why the hybrid

larkspur is an exceedingly popular flower, — particularly when

it is recalled that, in addition to its other merits, this is

a peculiarly hardy, thrifty, and prolific bearer.

ON SOME FAMILIAR COMPOSITES

type are of relatively immense size and of the most
wonderful color. But they do not produce so abun-
dantly as the common morning-glory, they do not
climb as well, and they seem to lack the vigor of
the ordinary form.

My experiments with the tribe have had to do
with the crossing of several related forms.

The plants can generally quite readily be
crossed, and the seed germinates readily. These
experiments have not been carried far enough to
produce any very striking results. It is obvious,
however, that the morning-glory offers good op-
portunities for improvement, and the ease with
which it can be cultivated makes it a plant that
should appeal particularly to the amateur. The
wide range of color variation, together with the
fact that the colors are fairly fixed in certain varie-
ties, make possible crossbreeding experiments that
can readily be checked.

Possibly also it may be feasible to cross the
morning-glory with the moon-flower or with vari-
ous other members of the genus. The moon-flower
itself, which produces large white flowers in great
abundance, has been greatly improved by selec-
tion.

There is also an interesting Brazilian morning-
glory (Ipnoea setosa) with a vine that grows with
great rapidity and bears a rosy purplish flower,

[183]

Variable Clusters

These specimens of hybrid larkspur are selected as sug-
gesting the considerable range of variation in the make-up of
the clusters of blossoms. Note the very striking contrast between the
cluster at the left and that at the right, the latter being the re-
sult of a long series of experiments in careful selective
breeding. Compare this picture with earlier ones
of this series, to suggest the full range of
variation in form and color among
the selected hybrid larkspur.

ON SOME FAMILIAR COMPOSITES

and a perennial tree morning-glory, a native of
Texas, which bears very large light pink flowers
in abundance. Indeed the number of species from
which selection can be made is rather large, and
variation among them sufficient to give the experi-
ment in hybridizing exceptional interest.

Another vine-like plant from South America
that has made its way into every garden is the
Tropaeolum, commonly known as the nasturtium.

There are at least forty species of this tribe,
mostly climbing natives of Peru and Chile. One
of these, T. puberosum, produces spicy roots that
are highly prized as foods, and its seeds are some-
times used in salads under the name of Indian
cress. The seeds of the form familiar in our gar-
dens are sometimes pickled, and it is probable that
table products of greater value could be developed
from these plants if attention were paid to breed-
ing them with that idea in mind.

Some of the nasturtiums are exceedingly tender
to the slightest chill, but they may grow in the
hottest and driest soil.

My work with the nasturtiums has been done
with specimens sent from South America by my
collectors, representing eight or nine species. Some
of these have bulbs that remain dormant in the
ground for two or three years, and then sprout and
grow very fine vines that climb over the bushes.

[185]

LUTHER BURBANK

The common nasturtium of our gardens, T.
ma jus, is one of the most readily grown of our
annuals and has been so long cultivated and so
thoroughly crossed that the colors of the flowers
are exceedingly variable. In recent years very
good work has been done, particularly by Cali-
fornia cultivators, in the improvement of the
climbing nasturtiums, and in particular by cross-
ing the ordinary form with the one known as T.
minus.

Both the parent forms and the hybrids have run
into numberless colors, clear lemon yellow, flesh
color, deep crimson, purple, scarlet, deep yellow
and white, the colors being variously blended, and
the foliage of the plant being sometimes most
beautifully variegated. Even the form of the leaf
has been changed, so that there now are ivy-leaved
strains of nasturtiums.

The nasturtiums offer great interest for the
amateur experimenter, as they are very readily
hybridized, and as their range of variation, even
without crossing, is so great as to afford the widest
opportunity for selection. Indeed, crossing has
been so fully carried out that for ordinary purposes
selection will answer far better than further cross-
ing. Indeed it is exceedingly difficult to keep the
colors of the various nasturtiums separate. The
seed of a pure white variety quite commonly may

[186]

California Morning Glory

This is one of numerous species and varieties of morning
glory utilized by Mr. Burbank in his experiments with this
flower. As some of the species come from the tropics, there is oppor-
tunity for the blending of widely different heredities.

LUTHER BURBANK

produce various colors. And it is more difficult to
fix these colors than is the case with most other
flowers. But of course such difficulties only en-
hance the interest of a really earnest experimenter,
and develop his enthusiasm.

STAMPING PERSONALITY ON A FLOWER
An illustration of the way in which the person-
ality of the experimenter finds expression in the
plants that he cultivates was furnished me a num-
ber of years ago by Mr. Peter Barr, a well-known
horticulturist who specialized with the narcissus
and daffodils.

On visiting my place a number of years ago, he
related an experience that may be taken as typical,
yet which the amateur who has not experimented
extensively might regard as rather extraordinary.
The story has been told in an earlier volume, but
it may be briefly repeated here.

Mr. Barr stated that among the thousands of
seedlings the whole stock of which he purchased of
two specialists in England, he could always tell at
once, on seeing the blooms, which of the two
specialists had developed any individual plant,
even though the varieties had been mixed.

One of the breeders produced very large, coarse
flowers, gigantic and broad, and lacking in delicacy
of contour. The other produced seedlings of
graceful and exquisite form.

[188]

A Bed of Hybrid Morning Glories

Here are some of Mr. Burbank's hybrid morning glories,
showing the not unusual propensity of hybrids to grow luxur-
iantly and bear flowers in profusion. This vine represents a stage
of progress, rather than the completed product.

LUTHER BURBANK

And these contrasting characteristics of the
different daffodils, Mr. Barr assured me, typified
the personalities of the two breeders by whom
they were developed. One of these was a person
of little refinement, notwithstanding his love of
flowers; the other was a cultivated banker of
artistic temperament. The tastes and propensities
of the two men made themselves felt in all the
flowers they produced; which of course was inev-
itable, when we reflect that the plants were pro-
duced by selection, and that each man naturally
selected the type that appealed to him.

I cite the incident not as something exceptional,
but as typical. Almost as a matter of course, one
could draw correct inferences as to the personality
of a plant developer from observation of the varie-
ties that he has developed — provided always, of
course, that his selections have been made along
the line of his own tastes, and not to meet some
specific commercial demand.

There should be for the amateur an added
stimulus in the reflection that he is thus putting
the stamp of his own personality upon the plants
with which he experiments. The flowers of your
own garden may thus come to have an individu-
ality that represents you as fully as you are repre-
sented by your costume or by the books you gather
on your shelves. And surely the possibility of

[190]

ON SOME FAMILIAR COMPOSITES

developing a flower garden that has such individ-
uality, differing from any and every other flower
garden in the world, should give the pursuit of the
amateur florist unique interest.

SOME INTERESTING NATIVES

I have more than once suggested the possibility
of introducing to the garden species of plants that
grow in the wilds and that offer interesting possi-
bilities of development. Two or three other tribes
of these interesting wildlings may be here referred
to. To name all that are worthy of consideration
would take many volumes for there are more than
ten thousand species of flowers indigenous to the
United States, and of these only something like
fifteen hundred have at one time or another been
placed under cultivation.

I may name two or three familiar ones, in addi-
tion to those that have already been referred to, as
offering exceptional attractions.

There are, for example, the Gilias, represented
by many species. I have cultivated twenty or more
wild ones at one time, selecting for brilliancy of
color, for size of flower, for compactness of growth,
or for some other desired quality.

On occasion I have carefully scrutinized at least
ten thousand different plants in order to select the
individual with which to begin improvements.

The gilias vary greatly in color, so that they are

[191]

A Wen; Burbank Morning Glory

Quantity production again, with ample opportunity for

selection, that the very best hereditary possibilities of the

hybrid may be revealed. The variety here shown is one of the newest

developments at Santa Rosa, as the morning glory

experiments are still in progress.

ON SOME FAMILIAR COMPOSITES

very interesting flowers with which to work, and
the colors may very readily be fixed in the course
of four or five generations. So also may the quali-
ties of compact growing, size of flower, and the
like. The plants, therefore, are encouraging ones
for the amateur who is anxious to get results.

The familiar milkweeds have been referred to
in another connection with reference to the pecu-
liar arrangement of their pollen masses, which are
so adjusted as to entangle the feet of bees.

The amateur will find it peculiarly interesting
to cross-pollenize these flowers. It will be ad-
vantageous to work with a magnifying lens of con-
siderable power. The curious form of the flower
and the unique arrangement of the pollen masses
give the work of cross-fertilizing these plants a
unique character, and these flowers are in general
among the most puzzling of all flowers for the
amateur.

There is possibility of developing, among the
milkweeds, plants of commercial value. I have
worked somewhat extensively with a number of
unclassified South American species. For two or
three years I carried on the work of selecting the
best seedlings among a large number, until several
races were pretty sharply defined. Now I am
crossing the best of these, the object being to get
varieties of more beautiful blossoms for garden

[193]

LUTHER BURBANK

culture, and also to secure varieties that will be
of value in producing a fiber that has something of
the quality of silk.

Even now tons of milkweed seed pods just
before they are ready to open are dried in the Mis-
sissippi Valley and shipped to Japan, where they
are used to make a kind of felt. In the Philippines
there is an allied plant, the Kapok, which supplies
a fiber much used for filling pillo\vs and the like.

It is considered within the possibilities that a
variety may be produced that will be of value for
the production of rubber, as the juice of some
species has excellent rubber qualities.

The native varieties of milkweed are exceed-
ingly hardy and as they are perennials they may
be worked on season after season. There is great
variation as to vigor of growth, size of leaves, com-
pactness of plants, and color and form of leaves,
as well as regarding the size, color, and abundance
of blossoms. The seed pods, with their white, silk-
like fiber also vary greatly. And there is corre-
sponding variation as to the amount of latex or
milk produced by the stalks.

All in all, then, there is scarcely another tribe of
plants that shows a wider range of interesting
qualities for observation of the experimenter.

Another wildling offering attractions of a dif-
ferent character is the so-called painted cup, or

[194]

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LUTHER BURBANK

Indian's paint-brush, classified by the botanist as
Castilleia.

The most familiar form of this plant is the one
known for its brilliant scarlet color. But the tribe
is exceedingly variable, and the different members
present flowers that range from scarlet, crimson,
orange, yellow, and purple to pure white. Some
are variegated. Individual plants of the first
named species growing on the same cliff along the
shore may show the widest range of variation in
the color of their blossoms. Indeed, all colors are
sometimes combined in the flowers of a single
plant.

In other cases one will find a small patch of
yellow flowers in one place, and in the neighbor-
hood another patch of orange colored or of white
ones.

The only color that is missing is blue. It would
thus be an interesting quest for some plant devel-
oper to see whether he could develop a blue
painted cup, somewhat as I was able to develop
a blue poppy. Even failing in this, the opportunity
to study heredity of color, and to isolate races of
painted cup of one color or another, attempting to
fix them so that they would come true from seed,
would give recreation for a number of seasons.

The fact that the painted cup does not always
prove easy of cultivation suggests that it is a plant

[196]

ON SOME FAMILIAR COMPOSITES

worthy the attention not merely of the beginner
but also of the amateur who has gained a measure
of experience, and who is willing to try his hand
at problems of plant development that are not free
from difficulties.

As I said before, it would be possible to extend
almost indefinitely this list of interesting flowers
that invite development. But the ones named may
serve by way of introduction, and the amateur may
readily extend the list by looking about in almost
any garden or by rambling almost anywhere along
country roads or in neighboring fields.

— The material lies everywhere
about us, and despite the activi-
ties of large numbers of flower
lovers, there are hundreds of
species readily accessible that
have never come under the
hand of the cultivator, and
which therefore have the
attraction of entire novelty.

fi

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Q «c 5

i? o o

ORNAMENTAL PALMS AND
CLIMBING VINES

VIEWS ON ARTISTIC TREATMENT

VISITORS from the East are often surprised
to find palms growing thriftily at Santa
Rosa. The average resident of northern
latitudes appears to associate the palm with trop-
ical conditions. And while it is known to everyone
that these trees grow in Southern California, it
seems a matter for wonderment that they should
be found so far to the north as the region in which
my experiment gardens are located.

In point of fact, isothermal lines make no dif-
ference in California, as the winds from the Pacific,
deflected by the mountains, determine the climatic
conditions, and produce quite unpredictable re-
sults. Thus it is that oranges are sold from north-
ern California before they are ready to pick in
the southern part of the state.

And again, the palm is a relatively hardy tree—
I mean, of course, in comparison with tropical

[VOLUME X — CHAPTER VII]

LUTHER BURBANK

plants in general. And whereas the date palm
does not thoroughly perfect its fruit, for the most
part, except in regions where the summer is very
long, this tree may withstand extremes of tempera-
ture that are widely removed from anything expe-
rienced in the tropics, and other palms generally
perfect their fruit wherever they can be grown.

Indeed, so hardy are some of the palms that the
question arises whether it may not be possible by
selective breeding and adaptation to develop races
of palms that will thrive even in the middle lati-
tudes of the eastern United States, and far to the
north of their present limits on the Pacific Coast.
The fact that most of the palms now growing in
California have been introduced within compara-
tively recent times, and that they have gradually
made their way northward, is suggestive of the
possibility of much wider extension of their
habitat

A difficulty in the attempt to carry out any
project in selective breeding calculated to give the
palm additional hardiness or any other quality is
found primarily in the fact that this tree does not
mature its fruit until from ten to twenty-five years
of age. But in recent years an effort is being made
by the Department of Agriculture and by several
private individuals, to introduce races of date
palms that will bear marketable fruit, and the

[200]

A Burbank Protege

This palm, now 44 year* old, was set out by Mr.

Burbank when he first came to Santa Rosa. It is a thrifty

specimen, and may be expected to outlive many human generations.

LUTHER BURBANK

study of the palm that has been undertaken in this
connection will doubtless lead to important results*
Even now it has been demonstrated that just as
good dates can be grown here as in the Sahara.

It appears that the palm, notwithstanding its
relative fixity, is subject to considerable variation,
and that this is particularly true of the date palm
fruit, as might be expected considering that this
tree has been under cultivation from pre-historic
periods, and because it has been selected for the
fruit alone.

The most delicate and delicious date fruits are
not the ones that can be secured for export, so that
these varieties can never be seen on the American
market until they are grown here. All the best
date palms, unlike most other palms, are grown
from suckers which come up from about the roots
of the tree.

To be sure, the Oriental peoples, for whom the
date has supplied a most important food product
from the earliest periods, have probably paid very
little attention to selective breeding. Still the broad
general fact that "like produces like" has been
matter of common knowledge from remotest
antiquity, and it can hardly be doubted that a cer-
tain amount of more or less intelligent selection of
the trees that bear the best fruit, with attempts to
raise seedlings from these trees and thus secure

[202]

ON SOME ORNAMENTALS

races of good fruit-bearers, has been practiced,
generation after generation.

Moreover a certain amount of cross-pollenizing
between allied races of palms has doubtless taken
place without the agency of man, and so it is all
but certain that the different palms under cultiva-
tion bear mixed racial strains, somewhat as do the
different races of orchard fruits and cultivated
plants of temperate climates.

It is quite to be expected, then, that the palms
grown from the seed should show a good deal of
variation.

That such is really the case is made obvious to
anyone who attempts to raise them. The date
palm, for example, may readily enough be grown
from the seed, for the seeds germinate readily,
though slowly. But the tests have shown that the
progeny of a date palm bearing fruit of the best
quality cannot be depended upon to transmit the
characteristics of the parent with a high degree of
certainty.

So it is necessary to grow the young trees from
suckers if the strain of the parent is to be perpetu-
ated accurately.

The experts of the Department of Pomology at
Washington and several private individuals, have
imported rooted suckers, obtained from female
trees known to produce fruit of excellent quality,

[203]

A Familiar Ampelopsis

There are several species of ampelopsis with which Mr.
Burbank has worked extensively. The spray here shown is
the familiar Ampelopsis quinquefolia, commonly known as the Vir-
ginia Creeper, and sometimes spoken of as the "five-leaved ivy."
Mr. Burbank has performed interesting hybridizing ex-
periments with members of the family and has
produced some rather important new varie-
ties of crossbred ampelopsis.

ON SOME ORNAMENTALS

distributing them and planting them in various
regions of the southwestern United States.

The trees that grew from these suckers have
proved to be pistillate, as expected, and produced
fruit equal to that of northern Africa. Consider-
able difficulty was experienced in securing suckers
from the best trees, even private individuals not
being allowed to own them in the original country.
As to the date palm, the progress already made in
the improvement of the fruit indicates beyond the
shadow of a doubt that still further improvement
will be made in many directions. It is probable
that the colony of fruit-bearers thus introduced
will spread indefinitely, until the date palm be-
comes an important economic tree in warmer
portions of America.

It is even more important with the palm than
with other fruit-bearing trees that propagation
should be carried out in this way, because when
the plants are grown from the seed only half of
them will be bearers of pistillate flowers.

The pollen-bearing trees will of course bear no
fruit, and while there must be here and there one
of these in the palm grove — one pollenate to about
twenty-five pistillate trees — it would be an obvious
waste of space to give over half the ground to
sterile trees. Yet there is no way of determining
whether an individual tree is a male or a female

[205]

LUTHER BURBANK

until it comes to the age of blossoming; and the
palm is a tree of slow growth that matures only
after a good many years.

But trees grown from suckers will be of the
same sex as the parent trees; hence the double
utility of propagating by this method.
PALMS FOR ORNAMENT

From the standpoint of the present chapter,
however, the fruit-bearing qualities of the palm
are not so much in question as its ornamental
character. Considered merely as ornamental
trees, there are members of the genus Phoenix, to
which the date palm belongs, that are more attract-
ive than this famous fruit bearer. And in general
the character of the form and foliage of a date
palm is carried with sufficient certainty from
parent to offspring by the seed to make it perfectly
permissible to raise palms from the seed for orna-
mental purposes.

Even where the seeds are planted in rows, with
the expectation of producing colonnades of palms,
along road sides or for borders, the palms may be
grown from the seed without danger that they will
vary sufficiently to interfere with the symmetry of
the row, provided the seed are gathered from the
same tree, or at any rate have come from the same
region.

If, however, the seed be imported from different

[206]

The Bottle-Brush Bush

This is a shrub from New South Wales; a rather tender
plant, but thriving out doors at Santa Rosa. It belongs to the
myrtle family. See the following picture in explanation of the pop-
ular name of this shrub.

LUTHER BURBANK

regions, there is probability of a good deal of
variation even among trees of the same species.

The more usual method, however, in California,
is to germinate the seed in a hothouse, growing the
young plants in pots at first, and then removing
them to boxes that they may be more readily
transplanted, as they make slender, wiry roots.
They are as easily grown as kernels of corn, though
requiring much longer periods of time. Occasion-
ally, however, they are planted in nursery rows,
and it is sometimes desirable to transplant them
after they have obtained a growth of twenty or
thirty feet in height, and a diameter of trunk of
one or two feet.

In such a case, it is necessary to cut around the
roots of the tree some time before removal, making
a ball of earth that is to be removed with the tree.
This treatment induces the palm to throw out new
roots, giving added firmness, and making provision
for the rapid absorption of moisture and nourish-
ment after transplantation.

A box being constructed around the soil, the
palm may be removed to any distance.

Sometimes a single palm thus transported is of
such size as to require an entire flat car. But
unless the precaution is taken to cut back the roots
and allow them to stand for some time before
removal, as just suggested, there is danger that the

[208]

ON SOME ORNAMENTALS

palm will die after transplantation, because the
loss of its long roots makes quick adaptation to
the new conditions impossible.

The Phoenix canariensis is a thoroughly hardy
palm in this climate, and the handsomest of the
hardy members of the tribe.

It is therefore the one most used for planting
for ornament in California, though the Chamae-
rops excelsior from Japan is as hardy and next
most common. The Canary palm grows with great
rapidity after the plant has the first five or six
leaves, although like all other palms its early
growth is slow. An ordinary specimen of this
species, transplanted into good soil in this region
when it has four or five leaves, will grow to a
height of fifteen feet, with a corresponding spread
of branches, and develop a trunk eighteen inches
in diameter in six to ten years.

No other palm with which I am acquainted will
make more than about one-fourth this growth in
the same time and under the same circumstances.

There is considerable difference in appearance,
however, and in rapidity of growth of different
strains of palms of this species. Yet the seedlings
are unusually true to type, so that long rows of the
Canary palms may be grown from the seed with
full assurance that they will not vary sufficiently to
break up the general uniformity of the row.

[209]

Blossom of the Bottle-Brush

A glance shows why this plant has received its popular

name. The technical name of the shrub is Callistemon, from a

Greek derivative, implying "the flower with beautiful stamens,'

There are several species of the genous, most of them hav-*

ing flowers with stamens of a beautiful scarlet color.

The one here shown is a selected variety

of Callistemon lanceolatus.

ON SOME ORNAMENTALS

Palms of the genus Chamaerops are also very
hardy, perhaps even hardier than the Phoenix
palms. I have never known one of them to be
injured by frost anywhere in California, even
when quite young.

There are several species of this genus. I have
grown them from the seed somewhat extensively,
and have noted a wide variation among different
species, some making large trees, while others are
dwarfs, some of which, in this region, never attain
a height of more than three or four feet. One
exceedingly thorny species may be multiplied by
division readily, as it throws up suckers abund-
antly around the old plant, unlike most other
palms. Some accidental hybrids have appeared
among the species of Chamaerops.

VARIATION AND DEVELOPMENT

Notwithstanding the considerable variation
among the different strains, there is almost no dis-
coverable variation in seedlings of a species of this
genus of palm when grown from seed of the same
tree. The species most commonly grown in Cali-
fornia is C. Excelsa. This is a species that in China
and Japan is one of the most useful of trees, its
foliage being used for thatch, the rigid leaf stalk
for braces, and the woolly substance about its
trunks for cordage and other purposes.

Moreover this is the palm from which fans are

[211]

LUTHER BURBANK

usually made, the undeveloped, immature leaves
being used for this purpose.

The palms of this genus usually bear the
stamenate and pistillate flowers on different trees,
but it is not unusual to find a few stamenate blos-
soms on pistillate trees, or, contrariwise, a few
pistillate blossoms on stamenate trees. This,
however, is a matter of no great practical import-
ance, since the trees are grown in this region only
for ornament, and it is not necessary to raise them
from the seed, as they put out suckers abundantly.

On the other hand, if the attempt is to be made
to hybridize the different species with the hope of
developing hardier races, the matter of fertiliza-
tion of the flowers becomes obviously important.

It will be worth while, then, to select the trees
with reference to those that tend to mature their
fruit early.

But the work of developing a race of hardy
palms will necessarily be a slow one, requiring the
co-operative labors of successive generations of
plant experimenters. And whereas it is probable
that in the course of a century or two hardy palms
will be developed, so that the question of selection
of ornamental palms will be of interest even to
residents of the middle and perhaps even of the
northern regions of the United States, at the mo-
ment the matter can have practical interest only

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for a limited number of people, and we need not
consider it more at length here.

It suffices to say that the methods of hybridizing
and selection that have proved successful with
other plants will doubtless be found to have full
application to the palm; and to add that the actual
work in this field has been begun only in a tenta-
tive way.

The method of hybridizing is simplicity itself—
as simple as crossing two varieties of corn.

Meantime, however, the palm exists as an orna-
mental tree of the very greatest value in California,
and the interest shown in it by tourists justifies the
expectation that in the near future, efforts of a
comprehensive character may be made, probably
under government supervision, to develop races of
palms that can be grown far to the north of the
present limits of this tree in the Eastern United
States.

A drive along Grange boulevard in Los Angeles,
for example, and inspection of its rows of palms,
alternating with pepper trees, gives the visitor
from the East a mental picture of the possibilities
of this race of trees for ornamental purposes that
should certainly stimulate a spirit of emulation.
Interspersed among pines — their brothers of pre-
historic times — they will be particularly appropri-
ate and look especially well.

[214]

ON SOME ORNAMENTALS

The ornamental value of palms for roadsides
and borders, and artistically placed here and there
on the lawn, is admirably supplemented by a back-
ground of vines growing on walls or over rustic
arbors or pergolas.

And of course there are numerous vines, as
everyone is aware, that flourish abundantly in
regions where the palm cannot be grown. So the
picturesqueness of effect that can be gained by the
use of vines sometimes better than in any other
way is available for the residents of northern cli-
mates, even far toward the arctic circle, almost as
fully as in the sub-tropical regions.

Among the vines that are so thrifty that they
will grow in almost any soil, and so hardy as to
resist the coldest winters, the so-called ivies of the
genus Ampelopsis take foremost rank. Of these
the Japanese Ivy, sometimes known as Boston Ivy
(A. vitchi) and its varieties, is probably the best
known and the most extensively grown. For the
purpose of covering brick and stone walls it is
perhaps the most beautiful of all vines.

This vine has a close rival, however, and in the
opinion of some even a superior, in the native
species familiar everywhere in the middle and
eastern states as the Five-Leafed Ivy or Virginia
Creeper. This vine, however, does not cling to
flat, smooth surfaces as does the Asiatic species.

[215]

LUTHER BURBANK

The strains of this vine differ materially in
different localities, there being one in particular,
named the Engdmanni, which clings to walls and
trees better than the ordinary varieties. Vines of
this variety are also far ahead of others in their
rapidity of growth and in the beauty of their foli-
age, and especially in their autumn coloring. Some
varieties hold their foliage nearly a month longer
than others.

These variations should be borne in mind in
selecting plants for the covering of walls or making
of arbors. The vines growing wild in Colorado
are, in my opinion, much superior to those of the
eastern states.

I have raised thousands of seedlings of both
species of Ampelopsis just named, and many speci-
mens of other species known respectively as A.
heterophyla and A. arborea, and have attempted
to hybridize them, but only recently succeeded.

The Japanese Ivy and the Virginia Creeper
have now been crossed by me, and it is expected
that the combination will produce varieties of
priceless value, giving opportunity for the develop-
ment of new races or ornamental vines to add to
the comparatively limited number now available.
The work is being carried forward on a large scale.
It is probable that the Ampelopsis and the grape
may be brought into combination.

[216]

Leaves of a Japanese Maple

This variety of Japanese maple is prized for the color of
the leaves, — and very justly so. There are other varieties, how-
ever, in which the leaves are curiously reticulate, some of them giving
the appearance of leaves that have been dissected so that only
the ribs remain. It would be of great interest to cross
maples of these two types, noting the results in
the first and second generations.

LUTHER BURBANK

Meantime, I have developed a new variety of
Virginia Creeper through selection that has much
larger foliage than the ordinary varieties, and that
is also a much more rapid grower, with the habit of
holding the foliage to a late period in the autumn.
As the plant is readily propagated by cuttings,
such a new race as this may be distributed indefi-
nitely.

THE BEAUTIFUL CLEMATIS

These vines are grown chiefly for their beauty
of foliage alone, although the grape-like berries of
the Virginia Creeper are not without some deco-
rative value.

There are other vines that in some respects rival
the Ampelopsis as climbers for the covering of
walls and arbors, and that have the added merit of
producing beautiful flowers. Notable among the
vines that have this double attractiveness are the
various species of Clematis.

There are several native species of the Clema-
tis, and the plant has been brought sufficiently
under cultivation to develop a propensity to vary.
Nearly all the species are rapid climbers, and pro-
duce beautiful flowers in astonishing abundance.
In addition some have feathery seed-pods that are
scarcely less attractive and interesting than the
blossoms that precede them, making an artistic
contrast with the foliage for a considerable period.

[218]

ON SOME ORNAMENTALS

So all in all the clematis must be ranked among
the most beautiful of vines.

My work with the members of this tribe has
been largely with the types that are known horti-
culturally as Jackmanm lanuginosa. These have
large blue and white flowers, sometimes inclined
to red and pink.

I have raised these plants very extensively from
the seed for many years. By selection, several
varieties were produced that bore very handsome
double flowers of peculiar form, varying in color
from blue, pink, and ashy gray to pure white. Some
of the new varieties also have exceedingly large
broad petals with the flowers of unusually rounded
outline, not unlike the form of a dahlia.

Several of the best varieties of these improved
Clematis vines were introduced through a dealer.
But it was subsequently related that the clematis
disease had destroyed most of these. This disease
is a kind of rot, usually ascribed to the same cause
that destroys lilies and many other plants in culti-
vated soil. It is probably bacterial, and is always
associated with thrips, millipeds, and eel-worms,
which probably serve to disseminate the germs.

Subsequently I began a series of hybridizing
experiments, using the Clematis coccinea as the
original seed parent.

This species is herbaceous and has scarlet,

[219]

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ON SOME ORNAMENTALS

flask-shaped flowers, with the sepals slightly
opened by the curling outward of their tips. The
sepals are thick and fleshy, although not leathery,
giving the flower almost the appearance of a fruit.

This species is almost invariable, about the
only diversity noticeable being a slight variation in
the size of the flowers.

To the pistils of several specimens of coccinea
was applied the pollen of various other species;
among these being C. crispa, known as "Blue
Bells", C. Davidiana, C. Fremonti, C. lig us tici folia,
C. Bouglasi, C. verticillaris, C. occidentalis, C. For-
tunei, C. Viticella, and others, no attempt being
made to keep the various crosses separate.

The hybrid progeny showed a great amount of
variation, especially as regards color of the flow-
ers. There were blue, crimson, scarlet, and white
flowers, and sometimes all of these colors appeared
in a single blossom.

There was also much variation within certain
limits in the form and texture of the flowers, which
in general were of a larger size than those of the
seed parent, and more spreading and widely open
in form. Some had thick sepals and some had
thin ones.

Perhaps the most striking peculiarity was that
the interior of the sepals often had a frosted ap-
pearance, due to the presence of a filament net-

[2211

LUTHER BURBANK

work of papillae. There is something of this ap-
pearance occasionally in flowers of C. coccinea and
C. crispa, but it was much accentuated in many of
the hybrids.

In their general habit and their herbaceous
stems, the hybrids seem uniformly to follow the
seed parent.

The flowers were produced in great abundance,
and the colors were not only most beautiful but
showed combinations never before seen in the
clematis. The bell-shaped flowers are for the most
part white on the inside, but exteriorly they are
crimson, pink, orange, blue, or purple. The beau-
tiful frosty throats give the flowers an appearance
that is unique.

I selected among the hybrids a few of the most
beautiful forms, and placed these, without specific
names, with a florist, Mr. J. G. Vaughan of Chicago,
for introduction. Some of my earlier clematis in-
troductions had been given names more or less
suggestive of their peculiarities of flower, includ-
ing "Ostrich Plume" and "Snow Drift". Another
had been named "Waverley".

I have stated that the earlier varieties were
destroyed by the clematis disease. In the later
experiments I endeavored to produce varieties that
would be immune to disease, as well as those that
would show exceptional hardiness.

[222]

ON SOME ORNAMENTALS

Several years ago, while on a trip in northern
Canada, I found patches of clematis on half-woody
slopes, growing in a region where the thermometer
sometimes goes fifty or even sixty degrees below
zero in the winter — regions where the deep wells
do not thaw out altogether during the entire sum-
mer, always having a coating of ice about their
walls.

The hardy clematis found in this region bears
dark blue flowers that are fully three and a half
inches in diameter, being about as large as those
of the cultivated varieties known as the blue Jack-
manni, the blossoms of which they also resemble
in color. There are two or three wild species in
the same regions, namely C. Fremonti and C. ligus-
ticifolia, plants that bear rather inconspicuous
flowers of a greenish white color, but having long,
feathery seed coverings that give them interest,
and being in addition strong growers.

I have already named these among the species
of clematis that were used in hybridizing experi-
ments.

It was to be expected that plants having strains
of such hardy species in their heredity would
develop some varieties of great hardiness. And in
this the expectations were not disappointed. A
more extended series of experiments than I had
planned to undertake would be necessary to fix

[223]

LUTHER BURBANK

the new varieties, and to make sure as to which of
them are the hardiest.

There is still opportunity for fine work in this
direction. The clematis is so beautiful a vine, and
there are so many species available, and among
these species such amazing variety of form of vine
and flower, that the opportunity for extensive
breeding experiments with this type is most invit-
ing.

In raising the seedlings my practice was to sow
the seed quite thickly in boxes in the greenhouse,
as soon as it ripened in the fall, forcing the plants
throughout the winter, and transplanting them in
the open field in the early spring. The seedlings
would make vines from eighteen inches to two feet
long the first season. They would rarely bloom
the first year, but in the second season they would
almost invariably do so and the general character
of their flowers could then be determined.

But the blossoms of the first season would not
fully represent the possibilities of their mature
production. For example, plants that first bear
blossoms that are semi-double would in later sea-
sons, when the vines had gained in strength, bear
fully double flowers.

At the time when my first hybrid double
clematis flowers were produced, there was, I think,
but one other double one known anywhere in the

[224]

Flowers of the Tecoma

There are more than one hundred species of this genous,
natives of temperate, tropical, and subtropical America, and
also of Asia and Africa. Owing to the shape of the flowers, they are
popularly known as trumpet vines. Some species, however,
are upright shrubs or trees. Mr. Burbank has hybrid-
ized several of the Tecomas with the Bignonia.

LUTHER BURBANK

world, this being a form produced in England.
More recently, however, several good double varie-
ties of this class have been introduced.

The clematis is a plant that improves with
acquaintance. Existing varieties furnish vines that
are beautiful in foliage, in flower, and in their pic-
turesque display of seed-pods. There is a great
variation among the forms already under cultiva-
tion, but there is still abundant opportunity for
improvement with these; and in addition wild
species may be found that through hybridization
will certainly introduce tendencies to still wider
variation.

What plant could offer greater inducements to
the would-be experimenter?

BIGNONIA, WISTARIA, AND BELL-FLOWER

Of the numerous other interesting ornamental
vines with which I have worked more or less ex-
tensively, I must content myself with mention of
only two or three. Not that there is lack of inter-
est, but to detail my work with them would involve
a needless repetition as to methods. The work
with the clematis may be taken as typical, and as
representing one of my most extensive single series
of experiments in connection with the ornamental
vines.

There are two or three other groups of vines,
however, that must be given at least passing notice.

[226]

ON SOME ORNAMENTALS

One of the interesting forms with which I have
done a good deal of work is the tribe of climbing
shrubby plants of North and South America of
the genus Bignonia. I have hybridized some
species of bignonia with several of the Tecoma, a
plant that grows wild in Virginia and Maryland.

The resulting vines were variable, and had a
fair degree of interest. There was modification of
color of flower, length of seed-pods, and vigor of
growth of the plants themselves. But no variety
was secured that seemed worthy of introduction.

An interesting feature of the hybridizing experi-
ments with the bignonia is associated with the
curious sensitiveness of the stigma of the flower to
irritation. The two lips of the stigma stand open,
like a set trap, and when pollen is supplied they
close, trap-like, grasping it instantly. Anyone who
has never seen the lips of the stigma of the big-
nonia close when irritated by bees or artificial
means would be greatly surprised.

It is necessary in applying the pollen to be
somewhat dexterous, lest the lips of the stigma
close and make the stigmatic surface inaccessible.

Nor may the lips be pried apart. They open
spontaneously, however, after a time, but usually
not until the patience of the operator has been
exhausted. It is a curious and interesting experi-
ment to irritate the stigmatic surface with a grass

[227]

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ON SOME ORNAMENTALS

stem or twig, which will be grasped as the trap-
like stigma closes, and held as a frog might hold
a stick in its mouth. The same remarks apply also
to the unrelated mulus, or monkey flower.

Good work may be done by crossing the hardy
bignonia with the tender ones, with excellent pros-
pect of producing new varieties of value.

Another ornamental vine that offers good op-
portunities for the plant developer is the familiar
and beautiful Wistaria.

There is a fair degree of variation among the
different species of wistaria, some bearing blue
flowers and others white ones. The plants of this
genus are not only valuable as climbers, covering
walls and arbors with vines that bear beautiful
flowers, but they can also be trained to form tree-
like bushes that are most attractive additions to
the lawn. The Chinese wistaria is ordinarily a
long vine, but may be trained to a bush five feet
across and thrive fully as well. Under this mode
of culture, a certain amount of energy that would
ordinarily go to the production of the vine itself is
saved and utilized for flower production, so that
wistaria bushes thus trained become astonishing
bearers of blossoms, like gigantic bouquets.

Nothing more is necessary in training the vine
than to trim it to form a head, and then from time
to time to cut out the straggling branches.

[229]

LUTHER BURBANK

The wisterias are difficult to hybridize, because
their flowers are papillionaceous, like those of the
peas and beans. But with a little care, hand-pol-
lenation may be effected, and some very striking
variations should be obtained in the second gener-
ation from a cross, for example, between the
American and Chinese wistarias.

A complex hybrid between these species and
the Japanese variety, Wistaria multiguga, which
produces astonishingly long racemes of flowers,
should give results of additional interest.

My own experiments with the wistarias have
consisted of the growing of a great number of
seedlings, both of the Chinese and American
species, selecting among these for plants varying
in form, and bearing blossoms of different size and
colors. The results of these experiments show that
the wistaria is an adaptable flower, and one that
is almost certain to repay more extensive breeding
experiments, in particular those that introduce the
element of hybridization.

I will name only one other type of ornamental
vines, this being the Lapageria, or Chilean Bell-
Flower.

As an excuse for selecting this one among many
tropical and sub-tropical forms, I may say that
when I first saw the Chilean bell-flower I thought
it the most beautiful flower of any kind that I had

[230]

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LUTHER BURBANK

ever seen. It has glorious, great, drooping, bell-
shaped, rosy or white blossoms, which no lover of
flowers could fail to admire. The foliage of the
plant is smilax-like, and somewhat deficient in
quantity, but the wonderful flowers make amends
for any defect of foliage.

Unfortunately the plants are very difficult to
raise, needing peculiar soil and much attention.
They are also sensitive to changes of temperature,
and do not bloom at an early age. Moreover they
must be kept moist at all times to insure good
growth.

The possibilities of work with plants of this
genus are shown in a remarkable cross said to have
been made by Veitch between one of the Lapage-
rias and the Philesia buxifolia, the latter being the
pollen plant. The hybrid which has been named
Philegeria Veitchii, is of exceptional interest, inas-
much as the parents belong to different genera.
In scientific interest it ranks with the blackberry-
raspberry hybrids, and the cross between the
amaryllis plants and their remote relatives.

As illustrating the possibility of the production
of interesting new forms, I may note that a col-
lector in Chile sent me a few years ago several
species oi plants allied to the Lapageria, but un-
classified as to species, that very much resemble
the English Ivy and that show exceptional habits

[232]

ON SOME ORNAMENTALS

of growth. One of these is said to bear excellent
fruit.

At three years of age, when the first blossoms
appeared, the strongest plants were about fifteen
feet high. Among the thousands of seedlings,
there is enough difference in the form of foliage,
rapidity of growth, and other characteristics to
show that the plant is susceptible of improvement
even in the first generation of seedlings from wild
stock

Experiments in hybridizing these new plants
with Lapageria, and further experiments in selec-
tion, in the hope of securing a new vine that com-
bines with other good qualities the property of
fruit-production, are contemplated. As yet this
series of experiments is only at its beginning, but
I mention it as illustrating one of the many lines
of investigation, looking to the development of new
varieties of ornamental vines, that invite the exper-
imenter.

— The clematis is a plant that
improves with acquaintance.
There is a great variety among
the forms already under culti-
vation and through hybridiza-
tion with wild species, still great-
er variation may be induced.

The Lippia

This is one of the plants that Mr. Burbank is testing as a
substitute for lawn grass. The species here shown is known
as Lippia repens. It will be seen that the plant makes a highly at-
tractive lawn cover in blossoming time. At other seasons it is a

mass of green that is a very good substitute for bluegrass.

LAWNS AND THEIR
BEAUTIFICATION

SOME OLD AND NEW SHRUBS AND GRASSES

PERSONS who have visited me at Santa Rosa
in recent years are almost always greatly
interested in the lawn about my dwelling.
At a little distance this looks very much like
any other lawn that is well-covered with grass.
But on closer inspection it appears that the lawn is
carpeted with a plant that is obviously not a grass.
It is in reality a species of verbena, very much
more closely related to the familiar flower of that
name than any other plant in cultivation.

This anomalous substitute for lawn grass is a
plant which was briefly referred to in an earlier
chapter as a relative of the verbena. It is known
as Lippia repens, and by some European botanists
classified as Lippia canescens. It is a plant indige-
nous to Chile, from which country I received the
seed from which the new lawn plant was developed
a number of years ago.

[VOLUME X— CHAPTER VIII]

LUTHER BURBANK

The value of the Lippias as lawn plants had
been shown by Dr. Francheschi, of Santa Barbara,
California, as long ago as 1900, he having intro-
duced a common form of Lippia repens from
Southern Europe where it had been grown as a
lawn plant by division until it lost its power of
producing seed, thus making further improvement
impossible.

The opportunity to improve the plant came
when my collector in Chile sent me seed of some
of the wild species. I saw that there was a good
deal of variation among the plants raised from this
seed, and in the following season raised about ten
thousand plants, each one of which was given a
little space in order that its individual peculiari-
ties as to rapidity of growth, tendency to spread,
and color of foliage might be studied.

From among some ten thousand plants about
half a dozen were saved, and the descendants of
these constitute several varieties of Lippias that
have marked peculiarities. A single cutting of one
variety will spread on an ordinary soil over a circle
about ten feet in diameter, in a single season.
This form would be very valuable for growing in
sunny places, in certain localities along irrigating
ditches, where the soil is subject to wash.

But I have more recently found two far better
substitutes for this purpose. One is the Mesam-

[236]

ON LAWN BEAUTIFICATION

bryanthemum, which grows on all seacoasts. This
produces an enormous amount of very heavy foli-
age, wrhich is not moved even by a strong stream of
water.

The other is the vine commonly called the trail-
ing myrtle (Vinca minor). This forms a great mass
of long white roots and long-topped vines with
abundant evergreen foliage, which resists stream
wash by shingling the whole surface so that the
water cannot reach the soil.

Another variety of seedling lippia grows only
half as fast, but has very fine dark green leaves
and lies very close to the ground, making a most
beautiful velvety lawn, while the older lippias
made a very unsightly lawn, though valuable for
dry climates. Unfortunately none are hardy in the
cold northern climates.

A third variety of lippia has pale green leaves,
is a slower and more compact grower, and makes
a lawn that contracts charmingly in color with a
lawn of the other lippias, or ordinary lawns of
bluegrass.

A fourth variety has long rope-like runners
growing in all directions, but not filling up the
spaces, and therefore not being suitable for lawns.
Still another has hairy leaves that give it a peculiar
frosty appearance, whereas the leaves of other va-
rieties are most often glossy.

[237]

LUTHER BURBANK

The foliage of these selected new seedlings vary
greatly in size, the leaves of some being several
times as large as others. The half dozen types se-
lected are being used for further development, and
as might be expected they show still more astonish-
ing variations in the second generation. A single
plant of some of the rapid growing varities usually
overgrows and covers up perhaps a dozen of the
smaller lippias of the same age.

Add that the new plants, in addition to their
rapid and compact growth, are adapted to dry soil,
requiring not one-tenth the water that blue-grass
or other ordinary lawn grass requires, and keeping
in good condition longer than any bluegrass or
clover lawn with a fraction of the care or the ex-
pense for watering, weeding, and mowing necessi-
tated by the ordinary lawn, and it is obvious that
the developed variaties of lippias constitute a very
important acquisition.

Curiously enough the lippia lawn makes a
better appearance where it is frequently trod upon
and subjected to treatment that would injure an
ordinary grass lawn, or destroy it altogether. The
plants appear to pay no attention if a path is made
directly over them; their appearance is actually
improved thereby.

With some species occasional runners may
grow above the main mass of foliage and become

[238]

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LUTHER BURBANK

unsightly, but these are readily cut away, leaving
a smooth velvety surface. These long runners
could be wholly prevented by cutting through the
plant diagonally at intervals of about two inches
with a machine similar to a strawberry runner
cutter, but with several blades.

The real difficulty that stands in the way of the
general introduction of the lippias as lawn plants
of altogether exceptional quality, however, is their
relative tenderness to frost. If selections result
in producing a hardy lippia, the plant will be wel-
comed everywhere, as it is already coming to be
welcomed in the warmer regions as one that solves
the problem of a lawn that will require practically
no attention, and yet maintain its greenness even
in long periods of summer drought. It must be
added, however, that during the wintertime it
turns brownish, and at that season it is not quite
as ornamental as a bluegrass lawn.

Until the lippia is further developed for hardi-
ness, however, it could not be used except in the
milder climates, and in the cold regions the blue-
grass and other allied grasses and the clovers must
be depended on for making lawns.

Meantime there are two of the new varieties of
lippias that have been introduced, and that are
rapidly making their way in California. One of
these, named Dixie, makes a most beautiful dark-

[240]

ON LAWN BEAUTIFICATION

green, close-growing lawn. The other, named
Mojave, has light-green foliage, in color not unlike
that of the older lippias, but is a larger and far
more rapid grower. This form is particularly val-
uable for quickly covering banks that are subject
to erosion from streams or heavy rainfall. It rap-
idly makes an impenetrable mat that resists the
invasion of water most persistently.

With all their tenacity in resisting storms,
drought, and constant tramping, these lippias do
not become weeds, as they produce no under-
ground stolons. By simple plowing or spading
they may be more readily removed than the or-
dinary lawn grass.

If left all summer without mowing, the lippia
lawn makes a rich bee pasture resembling some of
the handsome low growing clovers. If mown once
or twice it has the general appearance of a blue-
grass lawn, being soft and yielding to the tread like
a fine Axminster carpet. The lippias do not thrive
so wrell in the shade, being essentially sun lovers.
They turn brown during a few weeks in winter.
The two new lippias just described settle the lawn
question for sunny places in warm climates, as well
as the problem of very greatly lessening the wast-
ing of land by erosion on river banks and hillsides.

Meantime other experiments are being carried
on with various other plants which give promise of

[241]

LUTHER BURBANK

finally making good lawn plants. Among the most
interesting is a species of trailing Hypericum,
specific name unknown, from the mountains of
eastern Chile. As my lawn is an experimental one,
this has now supplanted the lippias there, and as
the new plant does not at any time turn brown in
the winter, like the lippias, it may prove superior
in beauty, though not quite as rapid in covering a
lawn surface.

Somewhat similar species of hypericum have
lately been introduced in my gardens from Russian
Siberia, and central and northern Europe, which
show a similar creeping habit, and no doubt will
be hardy everywhere. These, even in the first
generation from the wild native parent, show a
wonderful variation in rapidity and compactness
of growth, and from all appearance a few years'
work will give us a lawn plant for all climates far
superior to anything hitherto known, but probably
a little more difficult to get started.

All the hypericums will stand a great amount of
drought and ill treatment; they are unusually
hardy, stand tramping and mowing readily. No
doubt in future there will be produced varieties
that will be exceedingly valuable as lawn plants
for all climates.

Until the new plants have been perfected, how-
ever, the conventional lawn grass, with blue-grass

[242]

LUTHER BURBANK

at the head of the list, must be relied on in colder
climates. It is not necessary to refer to the com-
mon lawn grasses here in detail, their general
character and qualities being familiar to everyone,
and there having been no marked development in
recent years in the way of improving them.

It suffices to suggest that care should be taken
in buying seed from reputable dealers that grass
of good quality may be secured and the number of
weeds minimized. Beyond that it is hardly to be
expected that the interests of the amateur plant
developer will extend. For the grasses do not
offer opportunities for striking results in the way
of improvement that make them appeal to the
amateur. And, in any event, the blue-grass in its
best varieties constitutes a lawn grass of really fine
quality, and if properly cared for will produce a
lawn of a very satisfactory character. Mixtures
are never better, and seldom as good as the pure
Kentucky blue-grass lawn.

As to the matter of soil for the lawn, nothing
specific need be said beyond the statement that
the same sort of preparation is desirable that
would be used in preparing soil for field or garden
crops. Some details as to this will be given in the
succeeding chapter.

But I should like to offer a few practical hints
as to such preparation of the lawn as will ensure a

[244]

ON LAWN BEAUTIFICATION

proper regulation of the supply of air and water,
upon which the condition of the lawn so largely
depends. What is true about drainage and irriga-
tion will have equal application to land that is to
be used for raising flowers or vegetables or small
fruits. Indeed, my suggestions are based very
largely on my personal experience at Santa Rosa
in preparing the ground for the experiment gar-
dens on which plants of several thousand different
species, and representing many families from all
parts of the globe are grown.

A PRACTICAL DRAINAGE SYSTEM

Many hundreds of persons visiting my experi-
ment grounds at Santa Rosa each season have mar-
velled at the exceedingly varied and prolific crops
raised — exclaiming, "What a delightful soil you
have!"

Their surprise grows when they are assured
that this productive land was originally almost
valueless for growing plants. It was made fruit-
ful by artificial drainage and irrigation. The ap-
plication of the simplest principles of regulation of
water supply resulted in transforming a relatively
sterile soil into one of the most fertile areas of the
earth's surface. The method in which this was
accomplished may be outlined as offering a model
that may be followed to advantage in draining
similar land anywhere.

[245]

LUTHER BURBANK

Probably half the low-lying soils in the United
States could be made more productive by drainage.
Even if the soil of your lawns and gardens is fairly
productive, you may advantageously consider the
advisability of introducing such a system of drain-
age as that which we have employed at Santa Rosa
with such striking results.

The soil consisted of what is called adobe, a
black clay-like soil, said to be of volcanic origin,
and this particular piece cracked so during the
latter part of the dry season, that it was considered
unsafe to pasture stock on it, as it endangered the
legs of the animals, the cracks being often several
inches in width and apparently bottomless. No
crop had been grown here for years; and house
lots a mile or more out sold for about the price I
paid for the four acres.

Of course there is nothing novel about the
statement that the drainage of land is important.
The matter has been more or less understood since
the earliest periods. Yet a very large part of the
land of the United States that is given over to lawns
and gardens is left to depend entirely on natural
drainage, and fails to produce anything like the
crops that might be grown on it, if a more rational
provision had been made for adjusting the water
supply.

In California the value of drainage has been

[246]

Bouquet of Campion Flowers

This pleasing flower has been grown by Mr. Burbank and
improved by careful selection. The plant is hardy and prolific,
and there are numerous other species with some of which hybridiza-
tion might doubtless be effected.

LUTHER BURBANK

shown in the results obtained even with wheat on
fields drained and those not drained. Only one or
two ditches across a field have made it possible to
produce two or three times as large a crop as was
grown in the same field before the ditches were
made.

In a certain oat field in Wisconsin, the yield per
acre was doubled by drainage. The yield before
drainage was only sixteen bushels, but after drain-
age it increased to 32.3 bushels per acre.

There are at least two bad effects to be expected
from an oversupply of water. They are :

(1) An oversupply makes certain areas so soft
that they cannot be cultivated at all or at least not
until late in the spring.

(2) Air, which is essential to plant growth,
cannot enter the soil supplied with a superabund-
ance of water.

Air is as necessary to the roots of plants as
water and it is upon this principle that all systems
of cultivation and drainage are based.

The complicated chemical changes in the
growth of the plant cannot take place unless there
is sufficient of both air and water. Roots cannot
exist where there is a superabundance of water
in the soil.

There are several systems of drainage which
will not be discussed here. I consider underdrain-

[248]

LUTHER BURBANK

age with common drain tile the best system for
ordinary conditions, and it is with this system that
I have had most experience. The discussion is
given mostly from the viewpoint of results on my
own grounds.

Small, well-burned drain tile was used on my
Santa Rosa ground carefully laid with a slope of
1 foot to 40 feet and it has proven eminently satis-
factory in every respect for twenty years. The
soil is a heavy adobe and was almost worthless
before it was drained.

The good results of the drainage were scarcely
apparent the first year, but the benefits were mul-
tiplied each year until now the soil is easily culti-
vated and bears enormous crops while before
draining no crop could be raised.

This system consists of one main line of 4-inch
tile with laterals of two-inch tile every 40 feet.
The laterals gather the surplus water quickly after
a heavy rain and the main tile carries it to a small
stream near by.

The laterals do not need such a large capacity
as most people think. It must be remembered that
they work both day and night, and Sundays as well
as week days and a very small tile will carry a
great amount of water in the course of twenty-four
hours.

It is a good plan to have the tiles flushed now

[249]

ON LAWN BEAUTIFICATION

and then, and if they are not too large they will
sometimes be flushed during heavy rains when
they are filled to capacity. This flushing serves to
keep them clean and the flushing produced natur-
ally when small tiles are used is sufficient reason
for recommending the smaller sizes rather than
larger ones which are more expensive and gen-
erally less efficient.

The general impression is that cracks should be
left, and sand put in the cracks. The real way is
to surround the joints with clay; then they are
permanent. The worst thing to do is to put sand or
gravel or straw about the cracks. A tile four feet
deep will drain twice as wide an area as a tile two
feet deep. About four feet is the proper depth.

The strength of the entire system depends upon
the weakest section. Therefore it is necessary in
laying the tile to examine carefully each piece, and
to see that they are well burned, but not sufficiently
to make them impervious. The system must be
laid upon the proper grade, for if the line sags,
sediment will collect and retard the flow of water.

It is best to make a silt basin at some point
where the branching tiles unite. This is formed
by digging down a foot or two, and bricking or
cementing up a barrel-like receptacle, the entrance
pipe from the main system being a little lower
than the exit pipe, so that the silt settles.

[251]

LUTHER BURBANK

In the twenty years since the tile system was
laid at Santa Rosa, the tile itself has never been
exposed, or in any way touched or examined. It
continues to perform its function perfectly.

Drainage is really a science in itself, and there
is not enough space here to give a full discussion
of it. There are a number of good books upon
the subject, however, and the names of these will
be found in the chapter on reference literature.

Before the system is installed, some complete
treatise on drainage should be thoroughly studied.

In some cases it is possible to secure the aid of
a person who has had experience in laying drain
tiles, and where this is possible it is the best plan.
SUPPLYING WATER

Irrigation is closely allied to drainage. The
two systems are for a similar purpose — to regulate
the amount of moisture in the soil for plant growth.

Irrigation is needed in locations where there
is not sufficient rainfall to insure the growth of cer-
tain crops. In many places also where the rainfall
is sufficient but not well distributed, irrigation will
be profitable, especially in seasons of unusual
drouth.

For large tracts such as orchards and extensive
seed and vegetable gardens, the common practice
is to run water in large ditches with a system of
smaller ditches throughout the field.

[252]

ON LAWN BEAUTIFICATION

If such a system is properly constructed and
cared for, little is wasted because it is placed very
close to the point where it is needed.

For small areas, sprinklers are generally used.

The fault with most of the common sprinklers
used to irrigate small areas, such as lawns and
small gardens is that they do not distribute the
water evenly. Most of them cover a circular space
and there is always some part of the soil which has
too much water or too little. One of the most im-
portant points in irrigation is to have the water
distributed evenly.

Some flat or fish-tail sprinklers distribute water
quite evenly, but the newer system of overhead
irrigation known as the Skinner system is, in my
judgment, by far the best for small areas, and
possibly for all areas of any size.

This consists of a number of one-inch galvan-
ized pipes with nipples placed along the sides
about 12 to 20 inches apart. These pipes with the
nipples inserted are mounted upon supports about
6 feet above the ground. The pipes are connected
with the water supply and the water turned on
when needed.

Depending upon the pressure, this system will
distribute water evenly for a space of from 25 to 50
feet on either side of the pipe. The pipe may be
located between two beds so that it may be turned

[253]

A South American Flower

This strange flower with its unusual markings, was
grown from seed sent to Mr. Burbank by a South American
missionary- It is one of many such which have encouraged Mr. Bur-
bank to further experiments toward improvement.

ON LAWN BEAUTIFICATION

on its support and distribute the water on either
side. When advantage can be taken of the wind,
the water will be thrown almost twice as far as
when there is no wind.

This system has been somewhat modified to
adapt it to small areas where irrigation is not
needed often. Instead of mounting the pipes upon
permanent stakes, they are carried from one place
to another as irrigation is needed and placed upon
temporary supports or movable stands.

For greater convenience in handling the pipes,
the temporary supports are only about 4 feet high.
On the top of these is nailed a curved piece of sheet
iron in which the pipe rests. The movable
stands are made of galvanized pipe in tripod form
and can be made by any plumber.

The sprinkler pipe is attached to the water
supply by a rubber hose and the system operates
in the same way as when in a permanent location.

This system is patented but it is not expensive
to install. The pipes can be purchased at any
hardware store but the nipples and the tool for
drilling the holes in the pipe for the nipples are
patented and must be purchased separately. Many
of the seed houses, that handle tools in addition to
seeds, sell this irrigating system.

When this system is to be used on a lawn the
supports can be made more or less ornamental.

[255]

LUTHER BURBANK

The cost of irrigating lawns by this method is
far less than by the use of circular sprinklers, for
both time and water are saved and the lawn is
supplied with a more even distribution of moisture.

There is another plan of irrigation which is
known as the underground pipe or tile system.
This is not often used because the first cost is too
great. In some cases, however, it has proven to
be satisfactory.

The part of any sprinkler system that deteri-
orates most rapidly is the rubber hose. When it
can be replaced by iron pipe it should always be
done to save expense.

Where hose is used it is usually necessary to
purchase a new supply each season. Its first cost
is two or three times more than that of a galvan-
ized iron pipe and the pipe usually lasts from ten
to fifteen years. There are several other systems
of irrigation of lesser importance, but it is not
necessary to describe them here.

THE MENACE OF WEEDS

However well the soil may be prepared for
garden or lawn, and whatever the attention given,
the cultivated plants of every description are per-
petually menaced by the rivalry of weeds.

A weed may be said to be a plant out of its
proper place so far as the economy of man is
concerned.

[236]

ON LAWN BEAUTIFICATION

This does not mean, however, that it is out of
its proper place in the economy of Nature. Nature
has a use for weeds and in fact they have done
much good for man.

When crops were first cultivated, farmers
stirred the soil in order to destroy the weeds.
They did not then fully realize that stirring the
soil aided the growth of the crops. They did dis-
cover, however, that when the weeds were de-
stroyed much better crops were produced, and
thus the weeds forced farmers to stir the soil and
allow the air, so necessary to the plants, to circu-
late among the roots.

Now that the farmers have learned the real
reason for cultivation at the proper times, whether
there are weeds present or not, the destruction of
weeds assumes a different aspect.

Weeds are a detriment in many cases from the
fact that when proper precautions are not used
they take possession of areas of land so that it is
impossible to grow useful crops.

There are two general classes of weeds, annuals
and perennials.

Annual weeds reproduce themselves by seeds
which mature each season, usually in great abun-
dance. Perennials, in cold climates, although most
of them produce seeds, also perpetuate themselves
by storing food and living matter under the ground

[257]

LUTHER BURBANK

where the life of the plant is protected until spring.
Many perennials have underground stems which
are sent out in all directions. From each
node a new plant may grow under the proper con-
ditions.

It is obvious that such weeds are most difficult
to destroy because, although they may be pre-
vented from bearing seeds, they distribute them-
selves over large areas.

The handling of annual weeds is summed up
briefly in one sentence: Prevent the production
and the introduction of seeds.

But with perennials not only must the introduc-
tion and production of seeds be prevented, but the
entire plant must be uprooted and destroyed.

When perennial weeds have taken possession
of an area of land, they may generally be brought
under control by thorough cultivation during one
or two seasons. This often means that one or
more crops must be sacrificed. Every weed on the
entire area must be destroyed as soon as — and with
some kinds before — it appears above the surface.

The vitality and food provided by perennials
in most cases does not keep the plant alive more
than one season. The plant depends upon its store
of food being replenished by another growth each
season. If the leaves cannot develop above the
ground, so that raw food collected by the roots

[258]

ON LAWN BEAUTIFICATION

can be digested and stored again underground, the
plant cannot grow the following season.

Thus it is that by cutting off the plants
continually for an entire season as soon as they
appear above ground they will die out and not ap-
pear again on that area unless, of course, the seeds
are again introduced.

Most weeds are provided with greater facilities
for reproduction and distribution than cultivated
plants. Most weeds also have some special means
for distributing their seeds over large areas.

Many of them, such as cockleburs (Xanthinm),
sandburs (Cenchrus), burdock (Arctium) and
stick- tights (Bidens), have burrs surrounding each
seed which are made up usually of many hooks or
spines. These seeds attach themselves to the
clothing of persons and to the various domestic
animals, and are thus transferred from one locality
to another.

Many of the weed seeds such as the thistles,
wild lettuce, dandelions, etc., are provided with a
feathery portion which assists their carriage by
the wind.

Other seeds are borne in pods which, when
dry, open with a suddenness which throws the
seeds great distances.

Some seeds are borne in fruits which are
relished by birds and animals. The seeds in this

[259]

South American Grass

This is an unnamed grass from South America,
lich has interest because of the curious panicles (suggest-
ing Plumes of a bird of paradise), in which its seeds are grown.
This is one of a great number of grasses with which
Mr. Burbank has experimented.

ON LAWN BEAUTIFICATION

case are usually small and are provided with a
hard coating so that they are not destroyed by di-
gestion in the bird's or animal's stomach, but are
carried great distances and on reaching the ground
are usually in best condition to germinate.

Most weed seeds have the ability to retain their
vitality for a long time. Farmers who have plowed
fields deeply have sometimes noticed that a certain
weed which was present the year before plowing
disappeared entirely for two or three years only
to reappear again later. This was due to the fact
that the seeds were placed by the deep plowing
several inches below the surface, and when the soil
was plowed deep again they were brought nearer
the surface. In some cases, seeds have been known
to retain their vitality for twenty years or more.

Although weed seeds are provided with many
more contrivances to secure a wide distribution
than those here mentioned, this is not the only pro-
vision for their perpetuation. Living as they do
among many discouragements and difficulties it
has been necessary for them to provide protection
for the plants themselves against unfavorable
weather conditions and against animals. Some
weeds have the ability to withstand long and severe
drouths while others are able to grow where there
is a superabundance of moisture. Some are able
to withstand extremely low temperatures.

[261]

LUTHER BURBANK

Protection against destruction by animals is
afforded by spines, thorns, bitter juices, and
poisons.

Understanding these provisions of Nature for
the production and perpetuation of weeds it is
quite apparent that prompt and efficient methods
must be used by farmers and gardners in destroy-
ing them on first appearance.

A few mustard, thistle, or dandelion plants
which seem harmless because there are so few,
may spread to such an extent that in a few years
it will cost thousands of dollars to rid an infested
area from the pest which, if destroyed while still
few in numbers, would have cost only a few dollars
or dimes.

Weeds are much like a leak in a boiler or a fire
let loose. They are easily attended to at first, but
lead to destruction if proper attention is not given
in the beginning. Never is the old saying "A stitch
in time saves nine" better exemplified than in the
case of weeds.

As has already been intimated, many fields are
infested with weeds through the introduction of
the seeds in the seeding of the crops to be grown.
Weeds that thrive particularly well with certain
crops sometimes produce seeds so like the seeds
of the crop in size and appearance that it is often
practically impossible to separate them.

[262]

ON LAWN BEAUTIFICATION

In many sections a weed known as corn cockle
(Agrostemma) is a pest in wheat fields. So nearly
do the seeds of the corn cockle resemble the
kernels of wheat in weight and size that for a long
time it was almost impossible to separate the
cockle seeds from the wheat. This, of course,
caused millers a great deal of trouble for the corn
cockle seeds have a black shell about them which
discolors the flour. Finally a special machine was
constructed for the removal of cockle seeds.

The perennial morning-glory, commonly called
the devil's shoe string, has often palmed seeds off
for wheat among screenings fed to poultry, being
about the same size and has established itself on
much of the best soils in California.

The darnel (Lolium) commonly called cheat,
infests grain fields in some sections and so well
have the seeds masqueraded that many farmers
thinking their seed was thoroughly clean, later
found this weed and have said that the seeds
changed into wheat, barley, oats, or whatever the
grain happened to be.

This mimicry, of course, is developed by
evolution. That is, those seeds which are most
nearly like the seeds with which they are mixed
are overlooked in cleaning and remain to per-
petuate the race. After many generations of this
sort of natural selection, the seeds constantly

[263]

LUTHER BURBANK

approach the grain seed in form, size, weight and
color.

The seeds do not change their botanical
characters as farmers suppose, but having a hard
coat, may lie in the ground until a wet season when
the grain is destroyed and the darnel takes its
place.

Many states have long maintained official seed
inspection for purity. Now there is a United
States law of similar nature. These laws have
been so well enforced that there is not so much
danger now of infesting land with weed seeds as
was the case a few years ago.

Farmers who make a practice of buying grain
for seed from their neighbors or other persons who
have not had their seeds examined by inspectors
are likely to have their fields infested with noxious
weeds. From a small sample, the quantity and
kinds of weed seeds may be determined. This is
especially true of alfalfa, clover, and lawn
grass seeds.

If the sample contains weed seeds, it had better
be rejected for there are always weeds enough to
contend with without sowing more.

Grains, clovers, and grass seeds are far more
apt to have foreign seeds mixed with them than
any other class of seeds as they are usually
harvested by the wholesale, weeds and all, and it

[264]

South American Thistle

Mr. Burbank takes a great interest in the thistles. He

believes that they are capable of being developed into useful

commercial plants. Here is a South American species with which

he is experimenting, first endeavoring to remove its thorns.

LUTHER BURBANK

is only by careful screening that the other seeds
can be removed. With seeds of hoed crops, such
a condition does not exist.

It is impossible, of course, to give here a
complete description of all the different kinds of
weed seeds, but pictures are given in the natural
color of some of the most common ones. By com-
paring the seeds with these pictures it will usually
be possible to determine the kind of seeds that
are found in your locality.

Of course, one must always expect to find a
few foreign seeds in a sample of grain, but remem-
ber that the weed seeds cost the same price per
bushel as the oats. That is, if the price is $2.00 a
bushel for oats, you pay $2.00 a bushel for the
weed seeds which are not only worthless but a
detriment to the crop.

In orchards, especially in California, the two
worst weeds are wild morning-glory and a new
species of perennial amaranthus.

Both of these produce many long and persist-
ently sprouting roots. The morning-glory sends
its roots to great depths and has taken possession
of many acres of the best land. This, of course,
greatly reduces the production of crops and the
value of the land.

The overrunning of a field is due to the fact
that the owner of the land was careless in not

[266]

ON LAWN BEAUTIFICATION

destroying the morning-glories when they first
appeared. This weed spreads in all directions
like a fire and its spreading is increased by ordin-
ary cultivation, as small portions of the roots are
carried by the cultivator to other locations where
they soon grow into new plants.

It is extremely difficult to exterminate the
perennial morning-glory in orchards and vine-
yards because the ordinary cultivating machinery
does not run close enough to the rows. The only
way to exterminate this weed is to spend all the
time and labor necessary for one whole season in
cutting off the plants before they appear above
the surface. This may be done with a cultivator
made with sharp knives that run under the surface.
It will be necessary to go over the ground regularly
at least once a week. If this pest is allowed to
produce any foliage it gives the plant a new start.

The common amaranthus produces an enorm-
ous amount of small black seeds. It is an annual
and is often called careless weed, because it is
seldom found in abundance except on land that
has been carelessly cultivated. Thousands of seeds
are produced by a single plant and they come up
during summer and thrive especially well on rich
fertilized soils.

The common amaranthus, however, is almost
harmless when compared to the new perennial

[267]

LUTHER BURBANK

species which has lately been seen in many public
grounds, and is rapidly spreading to farms and
gardens. This new weed, unlike the annual, sends
down long slender roots deeply into the soil and
if cut off, no matter how deeply, will immediately
sprout with redoubled vigor.

But this is not the worst.

Like the annual, its sole object seems to be to
produce enormous quantities of seeds. This new
pest trails instead of growing upright and begins
to produce seed almost as soon as the plants
appear above ground. This seed production is
continued as long as the plant lives.

The only method of destroying this is to cut
off the first plants which appear, and apply a small
quantity of salt or sulphate of iron on the cut
portion of the root, at the same time burning every
portion of the plant removed.

Mustard, wild radish, and wild lettuce, though
annuals, are often difficult to exterminate as they
are abundant seed producers. The best method of
exterminating these is to destroy each plant before
they have time to ripen seed.

Usually it is possible partially to rid the land of
them by plowing it thoroughly early in the spring
and growing some cultivated crop.

Sheep sorrel or red weed, sometimes called
"shamrock," is another most persistent weed, very

[268]

ON LAWN BEAUTIFICATION

hard to exterminate if once established, especially
in lawns and moist shady places. It is a persistent
producer of runners, as well as seeds that are
projected a great distance when ripe.

It seeds abundantly when the plants are quite
young. When the seeds are ripe they are pro-
jected with great force in all directions. This is
best exterminated by unremitting destruction with
the hoe before the plants produce seeds.

There are numerous other smaller and more
insignificant weeds such as shepherd's purse, sev-
eral senecias, chickweed, and others which are not
as persistent as those already discussed, but which
should be kept well under control by thorough
cultivation if good crops are to be produced.

It should be borne in mind that weeds are
enormously prolific, and that their seeds go every-
where. So it does not suffice to keep your garden
weeded and your lawn well mown. It is necessary
also to pay heed to the weeds along neighboring
roads for their seeds will be no respecters of your
boundary lines.

You will be taking steps toward enhancing the
beauty of your lawn next season, and will be
lessening your work in the flower bed and vege-
table garden if you use scythe and hoe freely on
the weeds growing along the roadside everywhere
in the neighborhood of your garden.

[269]

The Siberian Lily

This interesting Asiatic plant is under observation in Mr.
Burbank's garden, and has been improved by selective breed-
ing as to the form and size of its spikes of flowers. It is an
attractive novelty on the lawn.

ON LAWN BEAUTIFICATION

No effort that you could bestow would have a
larger influence toward the beautification of your
next season's lawn, and the lightening of your
labors in next season's garden than that devoted
to the destruction of this season's crop of weeds,
wherever found.

FLOWERS; AND THE DISPOSITION OF TREES

Probably color is the most attractive thing
about flowers. Usually solid colors are more
attractive but harmonious combinations are almost
as valuable.

A graceful form probably comes next in
attractiveness.

Size and abundance of bloom next. Size does
not always happen to be an advantage. Some
flowers, as the heaths, are attractive because of the
smallness of the blossoms. In this case the small
size really adds gracefulness to the plant. Where
the blossoms are small more are needed to make
a good effect, so improvements on flowers with
small blossoms should be made along this line
where needed.

Everyone must be his own judge of harmony in
the colors of plants. Most fairly well educated
persons have a sense of harmony to direct them to
the combination of colors to work for.

White is harmonious with all colors. A deep
red is not harmonious with blue, except sometimes

[271]

LUTHER BURBANK

with a pale blue. The sense of distinguishing har-
monious combinations of colors has been more
developed since aniline dyes were introduced.
This is principally because with the aniline dyes
almost any shade of color can be made. Before
their introduction the unusual shades were not
often seen.

All the prismatic colors are beautiful and
attractive in their proper place. The delicate
shades of each of these colors are even more
pleasing to the average educated mind. Red is
the most insistent color. Yellow and orange are
next. White is insistent. Black is insistent.

In selecting flowers, I aim to pick those that are
striking, harmonious, pleasing, and new in respect
to color. In order to be able to select flowers for
color one must be thoroughly familiar with all of
the colors in each variety now in existence. Now
that there are more people working for new
varieties of plants it often happens that two or
more persons will develop new varieties almost
exactly alike at the same time. For this reason,
it is usually more advisable to work with plants
that are not so common. For instance, get seeds
and slips from foreign countries, or take wild
flowers and domesticate them.

Each new flower should be developed for some
definite purpose. Red is an appetizer even to the

[272]

Japanese Magnolia

The magnolias are well known shrubs or trees of great

ornamental value, owing to their very large and conspicuous

flowers. There are a good many species, some of which are very

hardy. The specimen here shown is a Japanese variety

that Mr. Burbank has under observation.

LUTHER BURBANK

birds. They will always eat the red fruit before
that of any other color. Red flowers are good for
the dining-room, and orange or yellow will serve
the same purpose almost as well. Delicate shades
are needed for the parlor, drawing-room, sleeping
rooms, and libraries. A pale blue is very good,
and pinks and combinations of pink and white are
especially pleasing. It is also desirable to have a
bright color occasionally in these rooms where
more quiet flowers are kept. This gives a dash
and spirit that is needed.

Practically all colors blend well with gray or
brown as a background.

Flowers banked around the foundation of a
house represent an unconscious exhibition of
advanced civilization.

Vines give a peculiar grace to architecture and
subdue unattractive colors. Green vines blend
with any color.

Flowers harmonize with surroundings and
subdue undesirable colors or forms. Borders of
flowers break the hard angles between a building
and the ground. Perpetual bloomers and peren-
nials are especially good near buildings. The tall
ones should be placed close to the buildings and
the small ones in front. The small flowers are
better for the beds on the lawn or near the street.
It is not well to put taller plants in bunches in

[274]

ON LAWN BEAUTIFICATION

front of the home. A single tall plant here and
there sometimes lends an artistic effect Usually
when tall plants are placed near the road, it is
best to have those with thin foliage.

Colors for yard planting should, of course, be
those that attract the inhabitants. It is never,
however, well to have a predominance of red.
Flowers about the house serve to keep those living
there in good spirits. They add a cheeriness that
tends to keep people happy. White is always a
good color. Blue is appropriate but must be
accompanied by red or yellow, otherwise it gives
a cold effect. Purples and deep crimsons do pot
always blend as well as other colors.

HEDGES AND TREES AND SHRUBS

The larger trees should be in the rear of the
house. Fruit trees should be back of the house or
to one side. The trees that shed their leaves
should be on the south and east sides of the build-
ings. This leaves the evergreens to protect during
the winter.

Trees with plenty of foliage should be planted
on the southwest to protect the house from the hot
sun in the summer. On large estates oaks and
elms and the larger trees may well be planted even
in front of the home. Evergreens, especially tall
ones, should usually be set out rather sparingly.
Do not put them too close to the house, as they

[275]

Chilean Wild Flower

' Burbank has received hundreds of wild flowers from
n»*i ,r^°£ part Of which are u™<med and unclassified.

Here is one that shows interesting peculiarities of petal that distin-
guish it in almost any company and give it the interest of
novelty. Also it is by no means lacking in beauty,
as a glance at the picture shows.

ON LAWN BEAUTIFIGATION

keep out the sunlight and make the house dark. A
number of evergreen shrubs are desirable to set
off the place.

Palms are good in a warm climate. Palms
must not be crowded for they will suffer from lack
of light and air, and will get out of shape. Usually
the best way is to plant an abundance of palms,
and later thin out those that are not doing so well.
Sometimes it takes a great deal of courage to cut
out part of the trees, especially if some of them
have become favorites, but it will be to the detri-
ment of them as well as other trees if the thinning
is not done at the proper time. Evergreen trees
and evergreen shrubs should be allowed to grow
close to the ground.

It may be of interest to add the names of a
few of the more desirable ornamental trees and
shrubs :

Trees for Street and Ornament: Arbor Vitae,
Big Tree, Lawson's Cypress, California White Fir,
Silver Cork Fir, Maidenhair Tree, Silver Pine,
Douglas Spruce, Tideland Spruce, White Spruce,
White Ash, Basswood, Birches, Kentucky Coffee
Tree, White Elm, American Holly, Magnolias,
Oaks, Maples, Walnuts.

Shrubs for Ornamental Planting and Lawn
Decoration: Black Alder, Andromeda, Japanese
Barberry, Button Ball, Spanish Bayonet, Choke-

[277]

LUTHER BURBANK

berry, Flowering Dogwood, Inkberry, Jersey Tea,
Laurels, French Mulberry, Pearl Bush, Wild Roses,
Strawberry Bush, Sumach, Sweet Pepper Bush,
Sweet Shrub, Wax Myrtle, White Fringe, Wistaria.
Shrubs for Windbreaks, Hedges, Berries:
Black Alder, Arrow Wood, Mountain Ash, Com-
mon Barberry, Chokeberry, Coral Berry, Flower-
ing Dogwood, Sweet Elder, Wild Grapevines,
American Hazelnut, Huckleberry, French Mul-
berry, Russian Olive, Osage Orange, Wild Yellow
Plum, Sassafras, Sweet Shrub, Waxberry, White
Fringe, Witch Hazel.

— A very large part of the
lawns of the United States is
left to depend entirely on nat-
ural drainage and fails to pro-
duce what might be expected
of it if provision had been made
for adjusting the water supply.

FIELD AND FLOWER
GARDEN

SOME PRACTICAL HINTS FOR THEIR BETTERMENT

MANY have thought that decreased yields
are always due to the exhaustion of
certain chemicals from the soil. This
is not always the case. In fact, it is seldom that de-
creased yields are due to the lack of plant food.

Plant origination, the highest type of work with
plants, has shown the underlying principles of
soils and their use. The results of fifty years' work
in getting big results from the soil are here
summed up in such a way as to show the
underlying principles of crop production.

These principles are applicable on every farm,
and may be applied in increasing the yield of
any crop.

Years ago farming and gardening were "hit or
miss" performances. Farmers tried methods be-
cause some one else had used them, and but few
of them knew the reasons for any of the operations.

[VOLUME X — CHAPTER IX]

LUTHER BURBANK

In order to understand how to select soils and
how to secure the best results from them, one must
know the underlying principles of productive
ability of soils and the methods used by plants to
secure food from them.

Farming is now considered a manufacturing
process. As a matter of fact, a farmer uses more
kinds of raw materials and produces more kinds
of finished products than any other manufacturer.
It is just as necessary that he select his raw
materials with extreme care as it is that the manu-
facturer of machinery select the most durable
kinds of wood and the strongest kinds of metal.

Farmers have sometimes been criticised for
not using more fertilizers but this is not always a
just criticism. Fertilizers are valuable in some
cases, but often a better physical condition of the
soil would make it possible for the plants to secure
enough food materials to increase the yield
materially without adding fertilizers.

Profit in crops depends upon the location of
the crops grown, the use to which the crops are
put, and the cost of fertilizing when fertilizing is
necessary. There are other things which affect
the profits, but these are the underlying factors.

No definite rules can be given about handling
the soil, for each one must work out his own
practice according to his own conditions.

[280]

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LUTHER BURBANK

The value of soil depends upon its texture, the
elements it contains, the exposure, location, nat-
ural drainage, the availability of the elements
required, etc.

A well-drained alluvial soil of fine texture is
the most productive with the average crop.
Furthermore, it is usually most durable in its pro-
ductiveness. That is, its valuable qualities con-
tinue to manifest themselves year after year.

Other things being equal, a field located in a
comparatively level valley or plain is more val-
uable than one on the side of a hill. Often the soil
on the side of the hill is rather thin and there is
always the danger of washing. Rains come and
carry the most valuable part of the field into the
valley below.

Of course, hillside fields are valuable for some
crops. In fact, in some cases, where the soil is
rich, even better results are obtained on the hills
than in the valleys. This is especially true in
California and semi-arid sections.

North and east slopes are usually best for late
crops, but the south and west slopes are always
better for early crops. A slope toward the sun
even of only one or two inches to the rod makes a
difference in earliness of a week or more. This
has been proven by many experiments.

The northern and eastern slopes hold the

[282]

ON FIELD AND FLOWER GARDEN

moisture longer but do not warm up so quickly.
For this reason they are able to withstand drouth
better, but never yield as early crops as the
southern or western slopes.

A clay sub-soil a foot or more below the surface
with a sandy surface layer is the ideal soil for
fruit trees. In fact, such a soil is good for most
any crop. If the sub-soil slopes sufficiently to
drain off surplus water, such a soil will always
produce good crops.

CHEMISTRY AND PHYSICS OF THE SOIL

Plants secure their food from the soil through
minute hair-like appendages on the roots, known
as root hairs. The roots thus serve only as canals.
The root hairs collect the food.

Because of the extremely small size of these
root hairs it is plainly seen that any food used by
the plant must be thoroughly dissolved before
being taken up. These root hairs are deciduous
like the leaves, and only active to any extent where
the leaves are in existence and active. All food
taken up by the roots is secured in solution and
this makes it necessary to keep the soil properly
supplied with moisture.

The presence of the proper chemical elements
and moisture, however, is not the only thing that
is needed for the root hairs to do their work well.
Air must be present in the soil or it will be impos-

[283]

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I3J&I1

ON FIELD AND FLOWER GARDEN

sible for the root hairs to secure the necessary food
for the plant.

The air in the soil must come from the surface
so it is obvious that it is always necessary to keep
the surface of the ground in such a condition that
it will admit air. Thorough cultivation and deep
plowing keep the soil in a loose condition.

In this connection an old English adage copied
from The English Ploughman fits in well.

"It is not so tiresome to plow well, sir; your
mind is interested."

Knowing that the plant's roots must have plenty
of air, one enjoys stirring the soil deeply for he
knows that by this method the crop will be
increased.

Cultivation must be frequent because the
surface of many soils has a tendency to become
rather hard and compact.

We may consider that there are minute tubes
leading from the surface down into the soil.
When the tops of these tubes are closed by having
the soil bake it is easy to see that the supply of
air is cut off. Stirring the surface, then, makes
a connection with the outside air.

Cultivation also goes far in keeping insects and
diseases under control. Many insects' eggs and
larvae and many disease germs are found in the
soil. When the field is stirred frequently, these

[285]

LUTHER BURBANK

are brought to the surface and exposed to the hot
sun and thousands of them are thus destroyed.

Soil is of a very complex composition, and
furthermore it is continually changing. A worm
burrows into the soil and in his way replaces and
rearranges thousands of soil particles.

As the root hair penetrates among the particles
of soil it affects a change.

The passing of moisture from one particle to
another makes changes which are of extreme im-
portance from the standpoint of fertility.

Because of this everchanging condition, it is
necessary to pay close attention to the cultivation
in order to keep the conditions as near uniform
as is possible.

A soil that is not given the proper care as to
cultivation often holds its valuable food elements
like a deposit in a bank that bears no interest.

Every business man knows that it is an
extremely bad policy to allow resources to lie idle,
but farmers too often do not consider the elements
in the soil as resources.

There are three important ways to make
available the supply of plant food in the soil : One
is by stirring the soil so that the air makes it pos-
sible for the root hairs to secure the elements.
Another is by supplying sufficient air and moisture
so that the elements in the soil will be dissolved.

[286]

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LUTHER BURBANK

And the third is by applying fertilizers which
supply the plant foods needed, in an available
form.

It does not always follow that when the yield
of a certain piece of land is small, that land needs
fertilizers. It is very often the case that the poor
yield is due to poor seed or shallow culture, or
other cause. If great care is taken in selecting seed
from the highest yielding fields year after year, one
will then know that when the small yield comes it
is due to something else.

I do not mean to say that it is not necessary to
fertilize, but I do mean to say that very often
expensive fertilizers are added when a thorough
stirring of the soil, drainage, or irrigation would
accomplish the same result.

Soil that is producing fruit crops needs less
fertilizing than that producing grain crops. The
fruits contain such a large percentage of water
that the essential elements of fertility are
exhausted from the soil very slowly.

On the other hand, the grain contains a large
percentage of the essential elements of soil fer-
tility and it is necessary to add fertilizers to grain
fields much more often than to orchards.

Now that the fertilizer manufacturers are
under government supervision it is safe to use any
good standard fertilizer on the market. Many ex-

[288]

ON FIELD AND FLOWER GARDEN

periments have been conducted to determine the
right element in which the soil is lacking and
supply that alone.

The analysis of soils has often proven of value,
especially in scientific researches, but it is not
practical for the average farmer to have a chem-
ical analysis made of his soil to determine what
kind of fertilizer should be used.

In practically every case good barnyard
manure gives excellent results. In the same way,
a fertilizer purchased on the market usually gives
the results desired. Because of the complexity of
the soil and the complexity of the requirements of
the plants so far as different elements are con-
cerned, it is plain to see that it seldom or never
happens that any one element is wholly elimi-
nated from the soil at a time.

Sometimes an element which appears to be
exhausted from the soil is merely in an unavail-
able form. The addition of other elements in
such a case, although they do not seem to be
needed, may produce the required results because
they assist the unavailable elements in changing
to an available form.

Nitrogen usually has the most immediate and
pronounced effect upon crops when it is applied
in fertilizers. Nitrogenous fertilizers always pro-
duce quicker results, and when it is desired to get

[289]

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ON FIELD AND FLOWER GARDEN

early crops, these are the ones to use, especially
in the early part of the season.

Nitrogen is quite often in the form of ammonia
in the fertilizer. Ammonia is very volatile and
escapes into the air rapidly if not properly in-
corporated. A commercial product that has a
strong odor indicates that the ammonia is escap-
ing into the air.

Use a fertilizer when it is absolutely necessary,
but make sure first that some cheaper process,
such as cultivation, irrigation, drainage, or rota-
tion of crops, will not accomplish the same result.

The physical condition of the soil in practically
every case is more important than the chemical
condition, that is, it has a more direct effect upon
the crops.

INCREASING CROPS BY ROTATION

Many flower lovers have been dismayed at
having a favorite collection of lilies almost entirely
destroyed by insects. Such a disappointment can
be generally prevented by moving the lily bulbs.

Great fields of grain, and large orchards of
valuable fruit trees have produced smaller yields
year after year 'until it was finally impossible to
grow a profitable crop at all.

The remedy is rotation.

Each grower must be his own doctor, however.
There is no short cut to profitable crop yields.

[291]

LUTHER BURBANK

They are obtained by the man who understands
the bad effects of growing the same crop on one
field year after year, and who knows that these
effects can be avoided by making a change in
crops.

Every horticulturist and every agriculturist
should study what follows carefully. It tells why
failures come, and why rotation forestalls such
failures.

There are at least four important reasons why
rotation of crops is necessary.

In the first place, insects which often gather in
great numbers about certain plants are destroyed,
or at least their number is reduced when other
crops are grown on the land. This is because
certain insects are adapted to depend upon certain
plants for their nourishment. Lilies and amaryllis
are often almost completely destroyed by such
insects as mites, small centipedes, wire worms, eel-
worms, etc.

Absolutely new, uncultivated soils seldom are
troubled. It is mostly in gardens where plants
from various quarters are grown that difficulty
occurs.

These pests gather around the lower part of the
bulb and if the bulbs are left in the same place
several years the insects often destroy them com-
pletely.

[292]

Blossom of Night Blooming Cereus

The improved plant on which this beautiful flower grew
is shown in the frontispiece of the present volume. Unfortun-
ately the night blooming cereus is too tender to be grown except as a
hot house plant in the colder climates of the eastern states;
but it thrives in California, and deserves greater
popularity than it has attained.

LUTHER BURBANK

Although this is not generally known it is the
common cause for the destruction of lilies. Many
have had beautiful lily beds exterminated and
have been unable to determine the reason. Some-
times by transferring the bulbs to another location,
if thoroughly disinfected before replanting, they
can be saved.

If ^gladiolus bulbs, for instance, are planted in
the same place year after year, they do not thrive.

Usually there are fewer and fewer bulbs as the
seasons progress, rather than more, and those that
are produced are much smaller than the bulbs
originally planted. The plants are also less
vigorous.

The third year the crop is almost a complete
failure. It is necessary to practice rotation of
crops with gladiolus.

The same thing is more or less true with most
other bulbs, as most of them have a bitter poison
or protective principle that repels these insects.
Some of them, of course, are not quite so suscep-
tible to the ill effects as others.

Various bacterial and fungous diseases also
attack plants that are grown in one place year after
year. These organisms, although they may not
be entirely destructive the first year or two, grad-
ually multiply and become a greater pest from
year to year.

[294]

f '

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A Beautiful Flowering Cactus

This is the cactus known as Opuntia basilaris, a low
spreading form that makes a very striking contrast with the
giant spineless opuntias in 3/r. Burbank's garden. The present spe-
cies is too small to be of any value as a forage plant, but its
flowers give it high rank as a border plant for the garden.

LUTHER BURBANK

When trouble arises from this source
remedy is to rotate the crops or, in other words,
move the crop infested to another location.

Fungous diseases are especially destructive in
potato fields. The potato scale, blight, and wart
are well-known diseases which can often be wholly
or partially controlled by the proper rotation and
the planting of uninfected seed.

The third cause for failures is the unfavorable
condition of the soil produced by the toxic sub-
stances thrown off from the growing plants. Plants,
like animals, give off waste matter which is not
only useless but poisonous to the plant itself, and
often to other plants of similar nature.

These toxic substances are often less poisonous,
and in some cases are beneficial, to other crops.
It is obvious that when waste products from a
certain crop have accumulated in the soil for a
number of years, that soil is not as well suited to
the crop as formerly. A change of crops prac-
tically always results in a more profitable yield
because the waste products of the first crop are
often not injurious to the second one.

The fourth cause, which is far less common
than the others, is exhaustion from the soil of
certain elements necessary to plant growth.

It is very seldom indeed that any one of the
elements necessary to plant growth is wholly

[296]

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LUTHER BURBANK

absent from any kind of soil. It does happen
sometimes, however, that an element is not present
in available form. The plant's roots, of course,
cannot take up certain elements that are in such a
form that they cannot be absorbed. When the
supply of material in the form that can be used is
exhausted, the plant does not thrive.

Quite often the failure of crops when it can be
definitely attributed to the condition of the soil is
due to an unfavorable physical condition rather
than an unfavorable chemical condition.

Rotation of crops always has an important and
essential effect upon the physical condition. When
alfalfa, cow peas, clover, or some other legume is
grown, the roots grow deeply into the soil and
when another crop follows, the fissures or canals
opened up by these deep growing roots are used
by the roots of the new crop, besides storing con-
siderable nitrogen. In this way it is much easier
for the following crop to permeate the soil where
there is plenty of moisture. The roots can develop
much more quickly and with less effort than if the
deep rooting crop had not been grown on the soil
before it.

It is quite evident that the addition of barnyard
manure has almost as much beneficial effect upon
the physical and bacterial condition of the soil as
upon its chemical condition.

[298]

The Camellia

This shrub was introduced many years ago from

Japan, and has attained great popularity. It has double

interest in that it is closely related to the shrub the leaves of which

furnish the tea of commerce.

LUTHER BURBANK

The effects of rotation are most astonishing as
shown by the results attained especially in Cali-
fornia when grain follows a corn crop. There is
usually fully twice the yield secured from the
small grain crop following a crop of corn than
when small grain follows a crop of small grain.

No doubt, the cultivation given the corn during
the summer has much to do with putting the soil
in the proper physical condition for plant growth.
This cultivation destroys more of the microscopic
organisms which are injurious to plant life, and
releases elements which otherwise would be
unavailable.

With the present varieties of plants, it will
probably always be necessary to practice rotation
of crops. But when plants are developed which
are resistant to the various conditions which have
been mentioned, rotation will perhaps not be so
necessary.

Already certain plants have been developed
which are resistant to numerous diseases and
insects. Varieties of grapes are grown which re-
sist the attacks of phyloera, and apples which are
resistant to the attacks of aphis are well known.

Peaches and almonds which are not subject to
curl leaf have been developed.

Plums which are not affected by the brownrot
and plum pocket are now on the market, also

[300]

Cactus Blossom

Although 3/r. Burbank's spineless cacti have been de-
veloped as forage plants and for their fruit, they deserve a
place in any garden for their flowers alone. Not only is the massed
effect of these flowers superb, but the individual blossoms are
beautiful to the last degree, as this picture testifies.

LUTHER BURBANK

cherries, pears, walnuts, and perhaps chestnuts,
which are resistant to blight.

Because of the value to be secured from crops
which need not be rotated, too much emphasis
cannot be placed upon the importance of develop-
ing new plants for this purpose which are resistant
to the various pests.

It will almost always be found that in fields
badly affected with some disease or insect there
are one or more plants which are not affected as
seriously as the rest of the crop. By selecting such
plants and perpetuating them by seeds or division,
a new variety may eventually be produced that is
resistant to the particular disease or insect which
caused the damage.

If resistant plants were developed many old
field and garden soils which have become worth-
less for certain plants could be made to produce
profitable crops. Such soils are quite often thor-
oughly infested with numerous insects and diseases
and the failure of crops is due more to this than
to the lack of proper chemical elements.

It is possible to get resistant varieties of vege-
tables, grains, flowers, and trees and the process is
the same in all cases.

Nature practices rotation of crops in the forest.
A forest of hardwood trees is almost always re-
placed by soft wood trees. After these have grown

[302]

LUTHER BURBANK

on the land for some years, they are replaced by
hardwood trees. And so the rotation continues.

This is not intended to be a complete discussion
on the rotation of crops. It is the principles which
underlie the practice that are of the most funda-
mental importance.

It is impossible to suggest any definite kinds of
rotations which will be applicable under all con-
ditions. Each person must familiarize himself as
much as possible with the underlying principles
and determine the rotation that is needed under
his own special conditions.

[END OF VOLUME X]

— The physical condition of
the soil in practically every
case, is more important than
the chemical condition;
that is, it has a more
direct effect upon the crops.

LIST OF

DIRECT COLOR PHOTOGRAPH PRINTS
IN VOLUME X

Acanthus p

The Acanthus 287

Alfalfa

Alfalfa Seed 243

Ampelopsis

A Familiar Ampelopsis 204

Balloon Flower

A Balloon Flower 6

Double Balloon Flower 9

Single and Double Balloon Flower 12

Double and Tending Toward Tripleness 15

Yet Another Step Toward Tripleuess 18

Cactus

A Beautiful Flowering Cactus 295

The Sea-Urchin Cactus in Bloom 297

Cactus Blossom 301

Calendula

Work with the Calendula 21

Educating the Calendula 24

A Bed of Burbank Calendulas 26

A Promising Pupil 29

Another Stage of Progress 31

Still Another Calendula Variation 33

Calendula of Real Distinction 35

Extreme Development of Another Type 37

LIST OF ILLUSTRATIONS (Continued)

Callistemon Pagc

The Bottle-Brush Bush 207

Blossom of the Bottle-Brush 210

Camellia

The Camellia 299

Campion Flower

Bouquet of Campion Flowers 247

Cereus

A Selected Night Blooming Cereus Frontispiece

Blossom of Night Blooming Cereus 293

Clematis

The Clematis 231

Crinum

A Burbank Crinum 143

An Improved Burbank Crinum 146

Hybrid Crinum 149

Seed Pods of the Crinum 152

Everlasting Flower

Australian Star Flower 137

A Single Australian Star Flower Plant 140

Fuchsia

California Wild Fuchsia 290

Goldenrod

A Spray of Goldenrod 75

Grass

South American Grass 260

Hydrangia

The Hydrangia 250

Iris

The Iris 41

Graceful and Attractive 43

A Broad Petalled Iris 45

A Spectacular Iris 48

LIST OF ILLUSTRATIONS (Continued)

Page

A Round Petalled Iris 51

An Iris with Pointed Petals 53

A Difficult Flower to Cross-pollenize 55

An Ingenius Mechanism 58

A Luxurious Type 61

A Japanese Iris 63

Seedling Japanese Iris 65

More Japanese Visitors 67

Unnamed Flowers from China 69

Selected Chinese Iris 71

Larkspur

Improved Hybrid Larkspur 169

Color Variations in Hybrid Larkspurs 172

A Brilliant Specimen 175

A Distinctive Cluster 177

A Flower Cluster of Many Colors 179

More Hybrid Larkspur Variations 182

Variable Clusters 184

Lilac

The Summer Lilac 220

Lily

The Siberian Lily 270

Lippia

The Lippia 234

Magnolia

Japanese Magnolia 273

Maple

Japanese Maple in Mr. Burbank's Yard 213

Leaves of a Japanese Maple 217

Milkweed

Seed Pod of the Milkweed 195

Morning Glory

California Morning Glory 187

A Bed of Hybrid Morning Glories 189

A New Burbank Morning Glory 192

Ophiopogon

Japanese Ophiopogon 164

LIST OF ILLUSTRATIONS (Continued)

PalmS Page

Decorative Palms 198

A Burbank Protege 201

Petunias

Some Burbank Petunias 118

More Burbank Petunias 121

Large, Graceful and Artistic 124

Pinks

Chinese Pinks 127

A Bed of Chinese Pinks at Santa Rosa 129

Selected Chinese Pinks 132

Pink Borders 383

Poppies

Chinese Opium Poppies t 155

Another Specimen of the Chinese Opium Poppy 157

A Hybrid Poppy 159

Giant Oriental Poppy 161

A Bed of Oriental Poppies 162

Primrose

An Improved Evening Primrose 73

Scotch Broom

The Scotch Broom 281

Spanish Broom

The Spanish Broom Bush 239

Sisyrinchium

The Golden Chile Sisyrinchium 228

South American Flower

A South American Flower 254

Star Flower

Australian Star Flower 137

A Single Australian Star Flower Plant 140

Tecoma

Flowers of the Tecoma.. 225

LIST OF ILLUSTRATIONS (Continued)
South American Thistle.., .. 265

Tigridia

The Interesting Tigridia 79

Hybrid Tigridia 82

Another Hyb-id Tigridia 85

Variant Hybrids 87

Seedling Tigridias 89

Another Bunch of Seedlings 92

Bulbs of the Tigridia 94

A Blue Tigridia 97

Tigridia Seeds at Wholesale 100

A Nameless Missionary Flower 103

Verbenas

Burbank Hybrid Verbenas 106

More Burbank Hybrid Verbenas 109

Burbank Fragrant Verbenas 112

A Bed of Burbank Verbenas 115

Vetch

An Improved Crown Vetch 284

Virginia Creeper

A Familiar Ampelopsis 204

Wild Flower

Chilean Wild Flower.. . 276

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