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A PILOT PLANTING TRIAL “=
ON A SOUTHWESTERN IDAHO
DEER WINTER RANGE

Dean E. Medin and Robert B. Ferguson

USDA Forest Service Research Paper INT-261
Intermountain Forest and Range Experiment Station
U.S. Department of Agriculture, Forest Service

USDA Forest Service
Research Paper INT-261
September 1980

A PILOT PLANTING TRIAL ON A SOUTHWESTERN
IDAHO DEER WINTER RANGE

Dean E. Medin and Robert B. Ferguson

INTERMOUNTAIN FOREST AND RANGE EXPERIMENT STATION
U.S. Department of Agriculture
Forest Service
Ogden, Utah 84401

THE AUTHORS

DEAN E. MEDIN is research wildlife biologist with the Intermountain
Forest and Range Experiment Station in Provo, Utah. He holds
a bachelor's degree in forestry from Iowa State University,
a master's degree in wildlife management from Colorado State
University, and a doctoral degree in range ecosystems from
Colorado State University. The research reported in this
paper was done at the Intermountain Station's research labor-
atory in Boise, Idaho.

ROBERT B. FERGUSON is range scientist with the Intermountain Forest
and Range Experiment Station in Provo, Utah. He received
his bachelor's degree in forestry from West Virginia Univer-
sity and his master's degree in wildlife management from
Utah State University. His former assignment was the study
of artificial revegetation of deer winter ranges in southern
Tdaho, while located at the Intermountain Station's research
laboratory in Boise, Idaho.

ACKNOWLEDGMENTS

The authors acknowledge the assistance of M. Newell, C. Ohs,
and members of the field planting crew, Garden Valley Ranger
District, Boise National Forest, Idaho.

The use of trade, firm, or corporation names in this publi-
cation is for the information and convenience of the reader. Such
use does not constitute an official endorsement or approval by the
U.S. Department of Agriculture of any product or service to the
exclusion of others that may be suitable.

RESEARCH SUMMARY

The 30-acre (12-ha) planting was designed to test the appli-
cability of procedures recommended for improving deteriorated deer
winter ranges in southwestern Idaho by artificial revegetation.
Secondary objectives were to compare: (1) two planting methods--
direct seeding and transplanting; (2) two browse species--antelope
bitterbrush (Purshia tridentata [Pursh] DC.) and wedgeleaf ceano-
thus (Ceanothus cuneatus [Hook.] Nutt.); and (3) two bitterbrush
seed sources--southwestern Idaho and northwestern Nevada--for
both the seeding and transplanting methods.

Competing vegetation was reduced by preparing scalps about
3-ft (l-m) square with hoes made from square-nosed shovels.
About 1,200 scalps per acre (3 000 per hectare) were prepared on a
spaced grid pattern of 6 ft (2 m) from center to center. Seeding
was done in late October and early November using hand-operated
seeders. Three spots were seeded near the center of each scalp
at a rate of 12 to 16 seeds per spot. Transplanting of bare-root
nursery stock (1-0) was done in April using planting spades. One
transplant was placed near the center of each scalp.

Overall, the seeding treatments had a sixth-year survival of
80 percent; transplanting treatments had a sixth-year survival of
62 percent. Survival was calculated as the percentage of scalps
with surviving plants. Seeded bitterbrush had better survival
than bitterbrush transplants. The converse was true for wedge-
leaf ceanothus. Bitterbrush from local seed sources, whether
seeded or transplanted, outperformed other plants significantly
in survival and nonsignificantly in height growth.

The findings support the notion that adequate technology is
generally available for revegetating southwestern Idaho deer
winter ranges, and that inconsistent results are at least partly
due to improper application of recommended procedures.

CONTENTS

Page
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INTRODUCTION

Large areas of southwestern Idaho deer winter ranges have declined in both acreage and
forage productivity (Holmgren and Basile 1959). Many factors have contributed to the decline.
Wildfire, insect infestations, rodents, overuse by livestock and big game, urban expansion,
agricultural development, road and highway construction, and water storage projects have been
among the most damaging impacts (Klemmedson 1967). Effectively improving the forage produc-
tivity of these winter ranges is a major challenge.

One way to improve winter ranges is through artifical revegetation--the direct establish-
ment of food and cover plants. Seeding or planting often is the only practical means of
restoring productivity where essential food and cover plants are lacking or sparse. Early
attempts to directly improve southwestern Idaho deer winter ranges through shrub planting
programs were mostly unsuccessful (Holmgren 1956). As a result, studies began for developing
the knowledge required for effective range restoration.

Holmgren (1954) evaluated 50 native and exotic browse species for their potential suit-
Ppilittyeror artificial revegetation. Of those, species, only four indicated promise, and only
antelope bitterbrush (Purshia tridentata [Pursh] DC.) was outstanding. Consequently, many
later studies dealt almost exclusively with bitterbrush.

These studies included methods of collecting and cleaning seeds, preplanting treatment
Of seeds (Casebeer 1954), season of seeding, seeding rates, depth of seeding (Basile and
Holmgren 1957), seeding methods and equipment, site preparation techniques, effects of plant
competition, influences of small mammals and insects, and effects of trampling and browsing.
Holmgren and Basile (1959) summarized these investigations and recommended species to be
planted, planting methods, planting locations, and methods of protecting and managing planted
areas.

Yet, shrub planting programs failed to achieve consistent results. Small experimental
plantings became well-established stands. Successes were uncommon on large plantings. Oper-
ational projects were scaled back to minor trials on limited areas.

Causes of failure are conjectural in most cases. Holmgren (1956) provided evidence that
competition for soil moisture from cheatgrass (Bromus tectorum L.) and other annuals was
particularly damaging. Poor quality seed, improper planting technique, high rodent and rabbit
populations, disease, insect depredation, frost injury, frost heaving, summer drought, and
trampling and browsing by hoofed mammals have been advanced as associated or additional causes
of poor stand establishment. Also, environmental conditions for shrub establishment on south-
western Idaho winter ranges are harsh, particularly southern exposures.

We wondered whether knowledge was in fact adequate for the task of revegetating those
winter range problem areas most in need of restoration. Our observations suggested that
research-tested and recommended procedures were adequate, and that inconsistent results were at
least partly due to improper application. To examine this, we established a carefully control-
led and supervised pilot planting on a representative area of deer winter range in poor
condition. We designed the planting to serve as a full scale test of the applicability of
recommended procedures, to help define problems yet unsolved, and to provide the basis for
additional experimentation. For the experimental function, we defined three specific objectives:
(1) to compare two planting methods--direct seeding and transplanting; (2) to compare two browse
species--antelope bitterbrush and wedgeleaf ceanothus (Ceanothus cuneatus [Hook.] Nutt.);
and (3) to compare two bitterbrush seed sources--southwestern Idaho and northwestern Nevada--
for both the seeding and transplanting treatments.

THE STUDY AREA

The planting was done on a deteriorated segment of potentially productive deer winter
range. This range once supported large stands of shrubs, mostly bitterbrush, that are now
gone from many parts of the area (Holmgren and Basile 1956). The 30-acre (12-ha) test area
is a topographic unit varying from lower toe slopes to a major ridge at the top (fig. 1) and
located between Nelson and Carpenter Creeks on the South Fork of the Payette River in Boise
County.

* Figure 1.--Pilot planting area between

, Nelson and Carpenter Creeks on the
South Fork of the Payette River, Boise
National Forest (photo taken October
1968).

Topography is typically steep and dissected. Slope gradients are between 25 and 80 per-
cent with generally south facing exposures. The elevation is from about 3,300 ft (1 010 m) to
3,800 ft (1 150 m). Soils are of granitic origin, coarse textured and loose, with low water-
holding capacity. Average annual precipitation is about 23 inches (60 cm), most of which falls
as snow in the winter. Summer rains generally occur as infrequent, scattered, high-intensity
thundershowers. Soil surface temperatures in the summer are high, with 140° to 158° F (60 to
70° C) common and maximums reaching 168° F (76° C) (Ferguson 1972).

Vegetation is dominantly annual with cheatgrass the most abundant component. Broad-leaved
annuals include storksbill (Erodium cicutarium [L.] L'Her.), ground smoke (Gayophytum
diffusum Torr. and Gray), prickly lettuce (Lactuca serriola L.), and Douglas knotweed
(Polygonum douglasii Greene). Bluebunch wheatgrass (Agropyron spicatum [Pursh] Scribn. and
Smith) and arrowleaf balsamroot (Balsamorhiza sagittata [Pursh] Nutt.) are the most common
perennials.

Although deer had yearlong access to the planting area, few were present during the summer
and early fall. Livestock grazing was not permitted.

Treatments, listed in top-to-bottom order of establishment within planting blocks, were
as follows:

1. Bitterbrush, direct seeding, southwestern Idaho seed source.
2. Bitterbrush, transplants, northwestern Nevada seed source.
3. Bitterbrush, transplants, southwestern Idaho seed source.

4, Wedgeleaf ceanothus, direct seeding, north-central California seed source.

wm

Bitterbrush, direct seeding, northwestern Nevada seed source.

6. Wedgeleaf ceanothus, transplants, north-central California seed source.

Starting at the lower edge of the tract, treatments were applied sequentially to two rows
of scalped planting spots each, covering the width of the tract on east-west contours. The
fixed arrays of six treatments (12 rows) were repeated contiguously up the slope until the
entire tract was planted.

Twelve well-distributed blocks, approximately 75-by-150 feet (23-by-46 meters) wide and
encompassing one set of six treatments each, were subsequently marked off for observation of
plant response. But the consistent arrangement of treatments for all blocks gave no design
protection against response bias that could result from top-to-bottom nutrient or moisture
gradients in the sloped blocks. Such gradients were expected to have a minimal effect, however,
within the rather short length of slope for each block. Also, this judgment appeared to be
supported by the data. Response magnitudes were generally inverse to the direction of expected
bias effect associated with treatment location. Thus, within-block bias effects were assumed
to be negligible and the data were analyzed as for a conventional randomized block design.

PLANTING METHODS
Direct Seeding

Seeding methods were essentially those recommended for bitterbrush by Holmgren and Basile
(1959). There were minor modifications based on recent findings.

Seed source.--Bitterbrush seeds were collected from Ada and Boise Counties in southwestern
Idaho, and from Washoe County in northwestern Nevada. Wedgeleaf ceanothus seeds were collected
from Shasta County in north-central California.

Seed treatment.--Bitterbrush seeds were treated with a mixture of Endrin (50 percent
wettable powder) and liquid Arasan 42-S (thiram fungicide). Endrin was applied at a rate of
1 percent by weight and Arasan at a rate of 4 percent by weight. Both chemicals were mixed
with diluted (9:1) Dow Latex 512R adhesive before application. Aluminum powder was used as a
coating to prevent caking. Wedgeleaf ceanothus seeds were soaked in water heated to 176° F
(80° C) to reduce hard seed coats (Grisez and Hardin 1967) and planted without Endrin-Arasan
treatment.

Seeding season.--Both species were seeded in late October and early November 1968.

Site preparation. --Competing vegetation was reduced by preparing scalps about 3-ft
(1l-m) square and 2 inches (5 cm) deep with hoes made from square-nosed shovels.

Seeding depth.--Both bitterbrush and wedgeleaf ceanothus were seeded at a depth of 1 to
Eos anches (2°5°to 3.5 cm) #(Basile and Holmgren 1957; Adams 1962).

seceding rate.--Three spots were seeded near the center of each scalp at a rate of 12 to
16 seeds per spot (Ferguson and Basile 1967). Schussler hand-operated seeders were used to
dispense seed and control planting depth.

spacing.--About 1,200 scalps per acre (3 000 per ha) were prepared on a spaced grid
pattern of 6 ft (2 m) from center to center.

Transplanting

Bare-root planting stock (1-0) of both bitterbrush and wedgeleaf ceanothus was obtained
from the Lucky Peak Forest Nursery, located near Boise, Idaho. Plants were lifted in early
April, sorted, and graded for an undamaged root system, undamaged tops, and adequate root
length and root:shoot balance. Polyethylene-lined kraft paper bags were used for cold storage
and transport.

Field planting was done in mid-April 1969 by experienced planting crews from the Garden
Valley Ranger District, Boise National Forest. Planting spades were used. Site preparation
and spacing were as described above for direct seeding.

DATA COLLECTION

Seedling emergence, survival, and height growth were recorded on each sample scalp and
tabulated separately for each plot (treatment), block (replicate), and site characteristic
(aspect, slope position, slope gradient, slope shape, nature of competing vegetation).
Survival during the first year (1969) was assessed at 2- to 3-week intervals from May 1 to
September 10. Second-, third-, and sixth-year survival was assessed in September each year.
Emergence percentage values were calculated on a per-scalp basis. Survival was based on the
total number of scalps with emergent seedlings. The height of the tallest surviving seedling
or transplant on each scalp was measured in September each year.

Probable causes of mortality were assigned for each seedspot or transplant. Criteria
used to identify the causes were similar to those of Gashwiler's (1971).

In the first-year survival assessment, soil samples were collected from six sites distrib-
uted throughout the planting area. Samples were taken at depths of 6, 12, and 24 inches
(15, 30, and 60 cm) on paired scalped and unscalped areas. Percent soil moisture was measured
gravimetrically. Maximum soil surface temperatures on each soil sampling site were recorded
ising thermopapers.

Weather data were summarized from U.S. Weather Service records at Garden Valley Ranger
Station, located 2.5 mi (4 km) from the planting site and at about the same elevation.

RESULTS AND DISCUSSION
Emergence

Emergence of bitterbrush from both the Idaho and Nevada seed sources occurred from the
second week of March until mid-April. Wedgeleaf ceanothus emerged from late March until the
end of April. Most of the bitterbrush seedlings emerged during the last week of March and
the first week of April. Wedgeleaf ceanothus emergence peaked about mid-April. Emergence
counts were made May 1.

Bitterbrush emergence averaged 99 percent for the Nevada seed source and 97 percent for
the Idaho seed source (table 1). Most of the seed spots had clusters of emergent seedlings.
There was little site variation in bitterbrush seedling emergence; lower slope sites had
slightly lower emergence values.

Wedgeleaf ceanothus emergence averaged 36 percent, significantly lower (P<0.05) than
bitterbrush (table 1). Many seed spots had a single emergent seedling. Emergence was highest
(66 percent) on lower slope sites and lowest (13 percent) on upper slope sites. We were
unable to identify the reason for the poor emergence of wedgeleaf ceanothus. A 600-seed
sample from each seed lot used in the planting was hand sown on a nearby site at the time of
the pilot planting. Two-thirds of the seeds were protected by a rodent-proof screen. Sixty
percent of wedgeleaf ceanothus produced emergent seedlings in both the protected and unpro-
tected plots. This was better than that exhibited by bitterbrush from either seed source
(20 to 40 percent emergence).

Table 1.--Average emergence (percent), survival (percent), and height (cm) of antelope bitterbrush and
wedgeleaf ceanothus seedlings and transplants!

eo

Survival? Height
Seed Planting Year Year Year Year Year Year Year Year
Species source method Emergence 1 2. 3 6 1 2 3 6

Bitterbrush Idaho Seedling 97a 99 98 96 94a il 24 26 55a
Bitterbrush Nev. Transplant -- 87 70 56 39c 16 31 DS, 55a
Bitterbrush Idaho Transplant -- 94 90 88 86b 16 32 28 57a
Wedgeleaf ceanothus Calif. Seeding 36b 79 59 53 47c 4 10 16 32b
Bitterbrush Nev. Seeding 99a 98 94 88 78b 10 23 19 54a
Wedgeleaf ceanothus Galak. Transplant -- 92 86 76 61d 19 24 26 37b

1Column values not having the same letter are significantly different (P<0.05). Comparison of treat-
ment means followed Snedecor (1956, p. 253). Arcsin transformation was used for percentages.

“Emergence percentage values based upon the number of scalps that had at least one emergent seedling.

3Survival percentage values for seeded scalps based upon the number of scalps that had emergent
seedlings; survival was calculated as the percentage of scalps with surviving plants.

Survival

With two exceptions, survival during the critical first-year growing season exceeded 90
percent (table 1). Seeded wedgeleaf ceanothus averaged 79 percent survival; bitterbrush trans-
| plants from the Nevada seed source averaged 87 percent survival. First-year precipitation,
soil moisture, and survival trends are shown in figure 2. Monthly means of precipitation and
temperature immediately preceding and during the growing season are compared with long-term
records in table 2. Growing-season precipitation was below normal except for the month of June,
during which rainfall was more than double the long-term average. July and August were almost
without rainfall. April-to-September temperatures were generally above normal. Soil surface
temperatures measured on the planting site were commonly above 150° F (66° C) in July and
August.

Table 2.--Comparison of 1968 and 1969 weather data with long-term records, Garden Valley Ranger
Station, Idaho

Precipitation Temperature
Departure Departure
pee a etal irom nommal 4 a Mean | from normad,
Se Elite = SS ---- TW-----
October 5.9) -0.4 8.8 -0.7
November 9.0 lt oa, 2x0 20
December 12 +236 -2.3 fone
January 18;..9 EO}: ere) +270)
February 4.7 -3.0 = a9 eo Pail
March 1.4 =5.5 Zu 2 - .8
April 15 -3.0 8.8 + .4
May 139 -2.6 14.3 #1).'6
June Sia, Oita 16.8 + 5.5
July wl Seni Z0R9 = ad
August .0 -1.0 PAN RS) +56
September ZEN) tae L754 pl BPRS)
Year 64.2 +4.0 9..:0 +0.6

on

BITTERBRUSH (Idaho)

J
BITTERBRUSH (Nevada)

2 95
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MAY JUNE JULY AUG. SEPT.
DATE

Figure 2.--Trends in first-year survival, precipitation, and soil moisture from May 1 to
September 10, 1969:

6

id

Rapid desiccation of soils with the onset of the dry season is characteristic of many
rangeland sites in southwestern Idaho. Soil moisture, after being recharged in June, dropped
to a season minimum of about 2 percent at the 6-inch (15-cm) depth in mid-August (fig. 2).
Soil moisture percentages were markedly higher under scalps than under unscalped areas (table 3).
First-year survival trends appear weakly correlated with soil moisture trends. The soil mois-
ture recharge in June may have prevented more steeply declining survival curves.

Table 3.--Average soil moisture content (percent) at three depths (cm) on scalped and unscalped
areas, 1969}

Date
Treatment Depth Eyal 5/14 S27 6/18 7/8 T/A. 8/20 O70
Scalped us) SS 6.4 5:5 Sine) 6.8 5.8 Ziad Ziad
30 ipod 6.8 es) SENS aS 4.4 S24 Si
60 8.0 8.0 Fil 543 ee 4.6 4.2 4.8
Unscalped tS) 4.3 2.8 Bir, 4.3 622 Braid 125 1.4
30 Soe, Si.9 $1.16 S42 hee 4.0 SO) Se)
60 Teall 6.0 Siac 4.0 6.4 4.4 5:6 Dal)

lEach soil moisture value is the average of six sampling sites distributed throughout the
planting area.

Sixth-year survival differed markedly between species, seed source, and planting method
ftable 1). Seeded bitterbrush had better survival than bitterbrush transplants. The converse
was true for wedgeleaf ceanothus. Overall, seeding treatments averaged 80 percent survival;
transplant survival averaged 62 percent. Bitterbrush seeded from local seed sources had a
Sixth-year survival of 94 percent, higher (P<0.05) than any other treatment. Bitterbrush from
local seed sources, whether seeded or transplanted, outperformed other plants significantly in
survival and nonsignificantly in height growth. Although rating standards for shrub plantings
are nonexistent, we suspect that few would be dissatisified with sixth-year survival rates from
ia to 80 percent (compare fig. 3 and 4).

Figure 3.--A pilot planting area before
planting (photo taken October 1968).

Figure 4.--The same area six growing sea-
sons after,planting (photo taken
October 1974).

Substantial differences occurred in average height growth between species at the end of
the sixth growing season. Bitterbrush, regardless of seed source, had better (P<0.05) height
growth than wedgeleaf ceanothus. There were no differences (P>0.05) in sixth-year heights
between the seeding and transplanting treatments of either bitterbrush or ceanothus.

Sixth-year survival and height of bitterbrush planted from local seed sources varied by
site (table 4). Survival was strongly related to topographic influences. Generally, the
higher survival rates were on lower and upper slope positions. This was true for both the
seeding and transplant treatments. Height growth followed a similar pattern except for a )
slower growth rate on the extreme upper slope position. ‘Season-long soil moisture trends
measured during the first year were highest on the lower slope sites.

Plants on slopes that were either horizontally or vertically concave or convex had higher
survival. Those slope shapes were generally associated with the upper and lower slope posi-
tions. Lower survival rates were found on vertically and horizontally straight mid-slopes.
Slope gradients under 65 percent and those with southeast aspects. generally had better bitter-
brush survival than steeper slopes and those facing south or southwest. There are exceptions
to these generalities and there is probably some confounding among the topographic variables.

Each scalp on, each’ of the 12 samplée.blocks;was.‘classified as to ‘the nature (annuals
perennial) of the proximate competing vegetation. There was a tendency toward lower bitter-
brush survival on those blocks having the largest percentage of scalps with predominantly
perennial competing vegetation (fig. 5). Most of the perennial competition was from bluebunch
wheatgrass and arrowleaf balsamroot. Ilolmgren (1956) documented the competitive effect of cheat-
grass and other annual vegetation on the survival of seedling bitterbrush. Our study was not
designed to directly evaluate the effects of plant competition. Nevertheless, thesdatawapelicace
suggest that perennial vegetation may have a stronger competitive influence on bitterbrush
seedling survival than annual vegetation. Apparently, scalping effectively reduces competition |
from annuals. But perennial plants near the perimeter of the scalp may extend their roots
farther laterally and deplete soil moisture throughout the growing season.

Causes of Mortality

Each time survival counts were made, we recorded the apparent causes of mortality that had
occurred since the previous observation, relying heavily on personal judgment. Because survival}
counts began on May 1, we probably missed early postemergence mortality.

Drought accounted for 36 percent of 3-year seedling mortality and 29 percent of 3-year
transplant mortality (table 5S). IHeat and frost heaving caused minor mortality.

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SEEDLING

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a 0. 755 ®
Y = 68,55 + 27. 36lle

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4 R?= 0.70
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5 ; _| 100

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Sy .x=7. 48
R*= 0. 32

70
60
0 10 20 30 40 50 60 70 80 90 100

PERCENT OF SCALPS WITH PERENNIAL- COMPETING VEGETATION

Figure 5.--Sixth-year survival of bitterbrush seedlings and transplants (southwestern Idaho
seed source) in relation to percentage of scalps with perennial competing vegetation.

10

Table 5.--Percentage of 3-year seedling and transplant mortality attributable to specific causes!

Seedling Transplant
Wedgeleaf Wedgeleaf
Bitterbrush, Bitterbrush, ceanothus, Aver- Bitterbrush, Bitterbrush, ceanothus, Aver-
Idaho Nevada California age Idaho Nevada California age
Cause N=159 N=307 N=140 N=606 N=90 N=284 N=151 N=525
Weather
Drought 42 35 32 36 38 29 25 29
Heat 1 0 0) 1 0 0 0
Frost heave 0 0 0 0 1 1 Z 1
Animal
Small mammal Ti i a 7 i 5 18 9
Insect 4 2 6 3 2 0 0 1
Trampling 14 10 8 11 3 1 3 2
Browsing 2 7 1 4 l 2 8 3
Disease
(damping-off) 3 2 0 2 0 0 0 0
Soil movement 1 1 0 1 0) 0 (0) )
Planting technique 0 1 0 1 9 4 2 4
Unidentified 26 34 46 35 39 58 43 51

lSeedling N is the number of seed spots to which a cause of mortality was assigned; transplant N is the number of
transplants to which a cause of mortality was assigned.

About 25 percent of seedling losses and 15 percent of transplant losses were caused by
animal activity. Trampling by deer and clipping, root cutting, and mound building by pocket
gophers (Thomomys talpoides Merriam) were mainly responsible. Wedgeleaf ceanothus transplants
were particularly susceptible to root cutting by pocket gophers. Trampling killed 11 percent
of the seedlings and 2 percent of the transplants. This difference was the largest of any
single cause of mortality between seedlings and transplants. Insects (mostly grasshoppers,
webworms, and cutworms) also killed more seedlings than transplants. The planting was aerially
sprayed (Malathion) in mid-July of the first growing season as part of an area-wide grasshopper
control program.

Browsing by deer killed 4 percent of the seedlings and 3 percent of the transplants. Most
of the browsing mortality occurred between the second and third growing seasons, a period
separated by a severe winter. A decrease in average shrub height for some treatments the
following year (year 3 in table 1) probably reflected the heavy browsing of that winter.

Damping-off fungi and soil movement accounted for 3 percent of seedling mortality. Four
percent of transplant mortality was attributed to poor planting technique; most of this was
from doubled-up root systems.

Although not reflected in table 5, we later observed winter injury and winter kill of
wedgeleaf ceanothus.

11

Costs

Costs of seeding and transplanting are compared in table 6. Total seeding cost per acre
was $204.75 ($505.92 per hectare). Total transplanting cost per acre was $232.56 ($574.65 per
hectare). Costs are expressed at approximate 1979 prices. Labor costs were computed on a
$5.00 per hour wage scale. Costs for tools, and travel and lodging for planting crews are not
included.

Table 6.--Estimated costs of seeding and transplanting treatments, 1979

Planting method Cost sper. acre Cost per hectare
Seeding
Seedbed preparation (scalping hoe) $°.120), 00 $ 296.50
Seeding (hand-operated seeder) 45.00 ES 10)

Seed (cleaned)

Bitterbrush 28.60 70.67

Wedgeleaf ceanothus 9.40 2525
Preplanting seed treatment! ea ey
Total § 204.75 $ 505.92

Transplanting

Seedbed preparation (scalping hoe) 108.00 266.86
Handplanting (planting spade) 68.00 168.03
Planting stock (1-0 transplant) 56.56 139.76
Total $ 232256 $ 574.65

lRodent repellent treatment of bitterbrush and hot water treatment of wedgeleaf ceanothus.

Seedbed preparation (scalping) was the largest single investment item, accounting for 59
percent of total seeding cost and 46 percent of total transplanting cost. Seeding was about
12 percent less costly than transplanting. The cost of seed was about two-thirds that of nursery
planting stock. Seed prices were $14.24 per 1b ($31.40 per kg) for bitterbrush and $28.48 per
lb ($62.80 per kg) for wedgeleaf ceanothus. Nursery costs were $47.13 per thousand graded and
packed 1-0 transplants.

CONCLUSIONS

The planting was designed to test the applicability of procedures recommended for improving
deteriorated deer winter ranges in southwestern Idaho by artifical revegetation. Subobjectives
were to compare: (1) two planting methods--direct seeding and transplanting; (2) two browse
species--antelope bitterbrush and wedgeleaf ceanothus; and (3) two bitterbrush seed sources--
southwestern Idaho and northwestern Nevada--for both the seeding and transplanting methods.

Although expensive, the pilot planting demonstrated that shrubs can be successfully estab-
lished by either seeding or transplanting methods in environments typical of many southwestern
Idaho deer winter ranges. Our investigation supports the notion that adequate technology is
generally available for revegetating winter range problem areas and that inconsistent results
are at least partly due to improper application of recommended procedures. The findings are
not conclusive because the planting was done under a single set of environmental conditions.
Adverse environmental extremes may cause planting failures regardless of the care used in
following procedural details.

PUBLICATIONS CITED

Adams, Lowell.

1962. Planting depths for seeds of three species of Ceanothus. USDA For. Serv. Res. Note

OA ape eeace sOOUtNWeSt FOr. and Range Exp. Stn., Berkeley, Calif.
Basile, Joseph V., and Ralph C. Holmgren.
1957. Seeding depth trials with bitterbrush (Purshia tridentata) in Idaho. USDA For. Serv.
ReSs-) bapwo4 Op. Intermt. For, and Range’ Exp. Stn..,. Ogden, Utah.
Casebeer, Robert L.
1954. The use of tetramine in bitterbrush revegetation. J. For. 52(11):829-830.
Ferguson, Robert B.
1972. Bitterbrush seedling establishment as influenced by soil moisture and soil surface
temperature. J. Range Manage. 25(1):47-49.
Ferguson, Robert B., and Joseph V. Basile.
1967. Effect of seedling numbers on bitterbrush survival. J. Range Manage. 20(6):380-382.
Gashwiler, Jay S.

1971. Emergence and mortality of Douglas-fir, western hemlock, and western redcedar

Seedlings. “Hors Sei. 17,/(2)3230-237.
Guusez, John Ps; and E. Es. Hardin.

1967. A germination study on seeds of five species of the genus Ceanothus occurring in

Oregon. Newsletter Assoc. Offical Seed Analysts 41(2):12-19.
Holmgren, Ralph C.

1954. A comparison of browse species for revegetation of big-game winter ranges in south-
wescerm Idaho. USDA For. “serv; Res. Pap: 53, 12 p. Intermt. For. and Range Exp. Stn.,
Ogden, Utah.

Holmgren, Ralph C.
1956. Competition between annuals and young bitterbrush (Purshia tridentata) in Idaho.
Ecology? 37 (Z)i:370=377 .
Holmgren, Ralph C., and Joseph V. Basile.
1956. Range revegetation and deer on the Payette. Idaho Wildl. Rev. 9(2):10-13.
Holmgren, Ralph C., and Joseph V. Basile.

1959. Improving southern Idaho deer winter ranges by artifical revegetation. Idaho Dep.

Eush- and Game; Wildl. “Bull. 3; 61-p.
Klemmedson, James O.

1967. Big-game winter range--a diminishing resource. Trans. 32nd North Am. Wildl. and

Natur. Res.-Cont. [San Franscisco, Calif., March 1967]. p. 259-269.
Snedecor, George W.
H956. Statistical methods. Sth ed. 534 p. Iowa State College Press, Ames.

Medin, Dean E., and Robert B. Ferguson.
1980. A pilot planting trial on a southwestern Idaho deer
winter range. USDA For. Serv. Res. Pap. INT-261, 13 p.
Intermt. For. and Range Exp. Stn., Ogden, Utah 84401.

The planting compared: (1) two browse species--antelope bitter-
brush (Purshta trtdentata [Pursh] DC.) and wedgeleaf ceanothus
(Ceanothus cuneatus [Hook.] Nutt.); (2) two planting methods—-direct
seeding and transplanting; and (3) two bitterbrush seed sources--
southwestern Idaho and northwestern Nevada. Overall, the seeding
treatments had a sixth-year survival of 80 percent; transplanting
treatments had a sixth-year survival of 62 percent. Bitterbrush
from local seed sources, whether seeded or transplanted, outper-
formed other plants significantly in survival and nonsignificantly
in height growth.

KEYWORDS: Purshta trtdentata (Pursh) DC., Ceanothus cuneatus
(Hook.) Nutt., seeding, transplanting, shrubs, site relations,
deer winter range.

Medin, Dean E., and Robert B. Ferguson.
1980. A pilot planting trial on a southwestern Idaho deer
winter range. USDA For. Serv. Res. Pap. INT-261, 13 p.
Intermt. For. and Range Exp. Stn., Ogden, Utah 84401.

The planting compared: (1) two browse species--antelope bitter-
brush (Purshia tridentata [Pursh] DC.) and wedgeleaf ceanothus
(Ceanothus cuneatus [Hook.] Nutt.); (2) two planting methods--direct
seeding and transplanting; and (3) two bitterbrush seed sources--
southwestern Idaho and northwestern Nevada. Overall, the seeding
treatments had a sixth-year survival of 80 percent; transplanting
treatments had a sixth-year survival of 62 percent. Bitterbrush
from local seed sources, whether seeded or transplanted, outper-

formed other plants significantly in survival and nonsignificantly
in height growth.

KEYWORDS: Purshta tridentata (Pursh) DC., Ceanothus cuneatus
(Hook.) Nutt., seeding, transplanting, shrubs, site relations,
deer winter range.

PESTICIDE PRECAUTIONARY STATEMENT

This publication reports research involving
pesticides. It does not contain recommenda-
tions for their use, nor does it imply that
the uses discussed here have been registered.
All uses of pesticides must be registered by
appropriate State and/or Federal agencies
before they can be recommended.

CAUTION: Pesticides can be injurious to
humans, domestic animals, desirable plants,
and fish or other wildlife--if they are not
handled or applied properly. Use all pesti-
cides selectively and carefully. Follow

recommended practices for the disposal of
surplus pesticides and pesticide containers.

POLLOW THE LASEL

U.S. DEPARTMENT OF AGRICULTURE

The Intermountain Station, headquartered in Ogden,
Utah, is one of eight regional experiment stations charged
with providing scientific knowledge to help resource
managers meet human needs and protect forest and range
ecosystems.

The Intermountain Station includes the States of
Montana, Idaho, Utah, Nevada, and western Wyoming.
About 231 million acres, or 85 percent, of the land area in the
Station territory are classified as forest and rangeland. These
lands include grasslands, deserts, shrublands, alpine areas,
and well-stocked forests. They supply fiber for forest in-
dustries; minerals for energy and industrial development; and
water for domestic and industrial consumption. They also
provide recreation opportunities for millions of visitors each
year.

Field programs and research work units of the Station
are maintained in:

Boise, Idaho

Bozeman, Montana (in cooperation with Montana
State University)

Logan, Utah (in cooperation with Utah State
University)

Missoula, Montana (in cooperation with the
University of Montana)

Moscow, Idaho (in cooperation with the Univer-
sity of Idaho)

Provo, Utah (in cooperation with Brigham Young
University)

Reno, Nevada (in cooperation with the University
of Nevada)