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THE UNIVERSITY 

OF ILLINOIS 

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ASPARAGUS YIELDS 

As ASected By Severity 
of Cutting 



By E. P. LEWIS 



UNIVERSITY OF ILLINOIS 

AGRICULTURAL EXPERIMENT STATION 

BULLETIN 401 

(April, 1934) 



RESULTS IN BRIEF 

SEVERE CUTTING of asparagus is injurious to both 
yield and market quality of spears. The injury increases 
in proportion to the severity of cutting, especially in the 
early life of the plantation. 

Cutting the asparagus bed during the first year after 
setting was not profitable under the conditions of this ex- 
periment. Even Plot 5, which was cut only two weeks the first 
year, gave lower total yields for the seven-year period than 
plots which were not cut until the second and third years. 
More severe cutting caused injury which, from all indications, 
was permanent. The experimental plantation was of average 
vigor, but even under very favorable conditions first-year 
cutting would not be advisable. The lower grade of spears 
resulting from severe cutting reduces the yearly income from 
an asparagus plantation. 

Light cutting of asparagus the second year and medium 
cutting the third year gave the highest yield and quality of 
the six different treatments used in this experiment. Cut- 
ting for four weeks the second year after setting reduced the 
yields. Under conditions of average vigor, such severe cut- 
ting would not seem advisable. 

If a plantation has made a very poor growth during the 
first and second years after setting, it may be advisable to 
delay cutting until the third year or at the most cut very 
lightly the second year, tho ordinarily there is no need for 
delaying cutting until the third year. 



Urbana, Illinois April, 1934 

Publications in the Bulletin series report the results of investigations 

made by or sponsored by the Experiment Station. 



Asparagus Yields As Affected By 
Seventy of Cutting 

By E. P. LEWIS, Associate in Olericulture 

ASPARAGUS ranks as one of the important truck crops in Illi- 
nois, tho the areas devoted to its production are centralized in 
a few counties. The value of the crop is greatest in Cook 
county (Table 1). 

In cutting asparagus there are two problems to be considered: (1) 
the length of cutting season for an established plantation that will give 
the most satisfactory yields over a period of years; and (2) the most 
desirable length of cutting season for a new plantation and the age of 
crowns when cutting should begin! Some growers cut the plantation 
as long as the market price for asparagus is high, without regard to 
future yields, while others are more conservative and stop cutting at 
the end of the normal cutting season. In Illinois the normal cutting 
season extends over a period of 8 or 9 weeks which, in northern sec- 
tions, would end about July 4. In a new plantation many growers 
start cutting the field the second year after setting while others do not 
start cutting until the third year. 

During the summer and early fall the green tops manufacture the 
food supply, a large proportion of which is translocated to the fleshy 
storage roots in late fall. This reserve is used to produce the next crop 
of spears. Shortening the growing period of the tops by excessive 
cutting would therefore restrict the supply of food that could be stored 
and consequently would reduce yields the following year. 

The experiment reported in this bulletin was conducted at the Cook 
County Experiment Station maintained by the University of Illinois 
near Des Plaines, Illinois. The object of the experiment was to de- 
termine the effect of severe cutting upon asparagus yields, especially 
during the early years of the plantation, and to determine the exact age 
of crowns when cutting should begin. 

OTHER EXPERIMENTS 

During the past few years, several experiments have been con- 
ducted in other states to determine the effect of severe cutting on the 
yield and quality of asparagus. Most of this work has been along the 

27 



28 



BULLETIN No. 401 



[April, 



TABLE 1. ACREAGE AND VALUE OF ASPARAGUS CROP IN LEADING 
ILLINOIS COUNTIES IN 1929 m 



County 


Number of acres 


Crop value 


Union 


1 Oil 


$ 98 288 


Cook 


755 


148 353 


Madison 


516 


126 000 


Pulaski 


492 


26 121 


Jackson 


397 


31 437 


La Salle 


215 


42 473 


Other counties 


1 278 


204 256 








Total 


4 664 


$676 928 









U. S. Census. 

line of extending the normal cutting season of an established planta- 
tion. In Iowa, Haber 1 has shown that cutting until July 15, which is 
approximately two weeks longer than the normal season, reduced the 
yield and quality of spears. In California, Jones 2 studied the effect of 
extending the normal cutting season two weeks. Results showed that 
yields were somewhat reduced even under the conditions of a long 
growing season. 

In regard to the degree of cutting of a new plantation, there is 
little information. Experiments in California by Jones and Robbins 3 
showed that if asparagus made a very vigorous growth the year of 
setting, it might be cut the following year for a short period without 
injury. However, in Illinois, where the growing season is shorter, 
some injury might be expected. 



PLAN OF ILLINOIS EXPERIMENT 

In the experiment reported in this bulletin, crowns of the Mary 
Washington variety of asparagus were grown during the season of 
1925 and set in the permanent field in the spring of 1926. There were 
18 plots, each consisting of a single row 375 feet long with 150 crowns. 
The rows were 4 feet apart with the crowns spaced at intervals of 2j/2 
feet. The depth of planting was 8 inches. 

During the first year, the customary cultivation was given and the 
furrows gradually filled in around the plants. No fertilizer was ap- 

'Haber, E. S. Effect of size of crown and length of cutting season on 
yields of asparagus. Jour. Agr. Res. 45, 101-109. 1932. 

'Jones, H. A. Effect of extending the cutting season on the yield of aspara- 
gus. Calif. Agr. Exp. Sta. Bui. 535. 1932. 

'Jones, H. A., and Robbins, W. W. Influence of cutting asparagus the first 
year after planting on production the following year. Amer. Soc. Hort. Sci. 
Proc. 23, 23-25. 1926. 



1934} 



ASPARAGUS YIELDS AS AFFECTED BY CUTTING 



29 



plied the first year. In all subsequent years the plots were disked in 
the spring and fall, 500 pounds of 4-8-4 fertilizer applied at the end of 
the cutting season, and ordinary cultivation practised during the cutting 
season. For three or four weeks after cutting, cultivation was con- 
tinued and a cover crop of oats was seeded each year about August 1. 
The cutting season started approximately May 5 each year and ex- 
tended for a definite number of weeks according to the outline shown 
in Table 2. Six different degrees of cutting were made in triplicate. 



TABLE 2. NUMBER OF WEEKS EXPERIMENTAL ASPARAGUS PLOTS WERE CUT 

EACH YEAR, Six DEGREES OF SEVERITY BEING REPRESENTED BY 

THE DIFFERENT SCHEDULES 

(Plants set in 1926) 



Plots' 


1927 


1928 


1929 


1930 


1931 


1932 


1933 


Cut third year 
1, 7. 13 








4 


6 


8 


8 


8 


Cut second year 
4, 10, 16 





2 


4 


8 


8 


8 


8 


2, 8, 14 





4 


6 


8 


8 


8 


8 


Cut first year 
5. 11. 17 


2 


4 


8 


8 


8 


8 


8 


3, 9. 15 


4 


6 


g 


8 


g 


8 


8 


6. 12. 18 


6 


8 


8 


8 


8 


8 


8 



















The plots were arranged in series of triplicates, as indicated here. In all subsequent tables the 
figures given for each plot are averages of the three replications. 



Plots were cut beginning the first, second, and third years after setting 
and for various lengths of time. Plots were harvested at intervals of 
one to two days depending on the rapidity of growth. The spears from 
each plot were graded and records taken as to number and weight for 
each grade. Three sizes were arbitrarily taken in establishing grades. 
No. 1 consisted of all spears over y^ inch in diameter, No. 2 from 1/4. 
to Yi inch, and "Strings" under 14 inch. All measurements were made 
close to the butt. In spears which were not circular in cross-section 
the greatest diameter was measured. Weight of spears was recorded 
on total length as cut and not after trimming. 

RESULTS OF DIFFERENT DEGREES OF CUTTING 
Long-Time Yields Reduced by Severe Early Cutting 

The severe cutting of asparagus during the early life of the planta- 
tion reduced subsequent yields, as shown by the figures in Table 3 
reporting the yields each year for the entire seven-year period. The 



30 



BULLETIN No. 401 



[April, 



economic returns from the six treatments were lowest where the most 
severe cutting was done (Table 4). 

First-Year Cutting Compared With Third-Year Cutting 
Cutting on Plots 5, 3, and 6 was started in 1927 and is designated 
thruout the discussion as first-year cutting since the plantation was set 
in 1926. A comparison of yields on these three plots with yields on 
Plot 1, on which cutting was delayed until the third year, is shown in 
Table 3 and Fig. 1. 

TABLE 3. YIELDS OF ASPARAGUS DURING SEVEN-YEAR PERIOD 
(Each plot consisted of ^29 acre) 8 



Plot 


1927 


1928 


1929 


1930 


1931 


1932 


1933 


Total 



Weight of spears 



1 


Ibs. 


Ibs. 


Ibs. 
10.58 


Ibs. 
49.97 


Ibs. 
97.33 


Ibs. 
158.5 


Ibs. 
151 5 


Ibs. 
467 86 


4 




5.90 


14.37 


72.61 


98.83 


170.5 


169 4 


531 53 


2 




12.27 


15.47 


55.78 


80.53 


135.8 


134.3 


434 . 2 1 


5... 


2.1 


14.13 


27.05 


48.85 


73.95 


132.3 


133.1 


431 51 


3 


5.7 


14.77 


20.33 


41.87 


61.58 


108.0 


110.8 


363.12 


6 


7.4 


16.30 


18.37 


31.99 


52.30 


92.7 


101.0 


320.09 





















Number of spears 



1 






383 


936 


1 508 


2 172 


2 290 


7 289 


4... 




212 


439 


1 310 


1 510 


2 186 


2 393 


8 051 


2 




479 


562 


1 109 


1 314 


1 899 


2 012 


7 374 


5... 


91 


552 


991 


1 147 


1 371 


1 932 


2 035 


8 119 


3 


249 


667 


733 


960 


1 146 


1 642 


1 764 


7 161 


6 


355 


786 


712 


811 


1 027 


1 424 


1 626 


6 742 





















Plots were 375 feet long with 150 crowns; rows 4 feet apart: crowns spaced at 2 H-foot intervals. 

Plots 5, 3, and 6 received respectively, light, medium, and heavy 
cutting for the first and second years, while Plot 1 had two full years 
to become established before cutting began (Table 2). 

Weight and Number of Spears. Each of the three plots on which 
cutting was started the first year ( Plots 5, 3, and 6) gave a lower total 
yield for the seven-year period in weight of spears than Plot 1, which 
was given two full years to become established (Table 3). Plot 5 
gave a greater total number of spears for the seven-year period than 
Plot 1. Differences in yield, however, are more significant for weight 
of spears than for number of spears. Furthermore the income from 
asparagus is more dependent upon weight of crop harvested than on 
number of spears. 



1934] 



ASPARAGUS YIELDS AS AFFECTED BY CUTTING 



31 



TABLE 4. GROSS INCOME ON ACRE BASIS, ACCORDING TO GRADE OF ASPARAGUS, 

FOR SEVEN-YEAR PERIOD FROM PLOTS CUT WITH VARYING 

DEGREES OF SEVERITY 



Plot 


Number of crates per acre* 


Gross income per acre b 


No. 1 


No. 2 


No. 1 


No. 2 


Total 


1 


706 

825 
648 

611 
503 
321 


278 

299 
265 

285 
224 
241 


$ 948 

1 105 
868 

820 
674 
430 


$311 

335 
297 

319 

2S1 
270 


$1 259 

1 440 
1 165 

1 139 
925 
700 


4 


2 


5.. . 


3 


6 





The number of crates in each grade are calculated on an acre-basis at a weight of 12 pounds per 
crate. A 10 percent deduction in weight was made for the butts, which were cut off in trimming for 
market. Each plot equaled !i acre. 

*>The prices are taken from Chicago South Water Market for 1927-1933: No. 1, $1.34 per crate; 
and_No. 2. $1.12 per crate. 



An analysis of Fig. 1 shows the following facts: 

1. The number and the weight of spears on all plots for the first 
two years were in direct proportion to the number of weeks cut. 

2. In the third year, Plot 5, which had been cut the lightest of the 
three plots cut the first year, surpassed Plots 3 and 6, the less severely 
cut first-year plots, in both number and weight of spears. 

3. By the end of the third year, Plots 5, 3, and 6 gave higher total 
yields for the first three years than Plot 1, which was not cut until the 
third year. This difference in yields would be expected, of course, 
since the yields from Plot 1 represent only one year's cutting and the 
cutting was for a shorter period than on the other plots. 

4. Beginning with the fourth year, Plot 3, the medium-cut first- 
year plot, produced each year a greater number and weight of spears 
than Plot 6, the most severely cut first-year plot. 

5. For the last three years of the experiment Plot 1 gave higher 
yields than Plots 5, 3, and 6 in both number and weight of spears and 
a greater total yield in weight for the entire period. 

Plot 1 will probably continue to outyield Plots 5, 3, and 6 both in 
number of spears and in weight of spears per crown, since the yields 
have run almost parallel during the last three years of the experiment. 
Altho the differences in favor of third-year cutting do not appear 
great, more significant differences would result if they were expressed 
as acre-yields. 

It is evident that unless a plantation makes a very vigorous growth, 
cutting for even a short period the first year after setting is detrimental 
to yield of spears. 



32 



BUI.I.F.TIN No. 401 



160 




1927 I92S 1929 '930 1931 1932 1933 



FIG. 1. EFFECT OF FIRST- YEAR CUTTING ON WEIGHT AND NUMBER OF 
ASPARAGUS SPEARS, 1927-1933 

Of the three plots cut the first year, Plot 5 was given light cutting; Plot 3, 
medium cutting; and Plot 6, heavy cutting. Plot 1 was not cut until the third 
year. Both weight of spears and number of spears are in inverse proportion to 
the number of weeks the plots were cut, except for the first two years. All 
three plots cut the first year gave lower yields, as measured by weight of spears, 
over the seven-year period than the plot cut for the first time the third year. 



1934] 



ASPARAGUS YIELDS AS AFFECTED BY CUTTING 



33 



200 




1927 



1928 



1929 



1930 



1931 



1932 



1933 



FIG. 2. EFFECT OF SECOND-YEAR CUTTING ON WEIGHT AND NUMBER OF 
ASPARAGUS SPEARS, 1927-1933 

Plots 2 and 4 were cut for the first time the second year, while Plot 1 was 
not cut until the third year. Plot 4, which was given lighter cutting than Plot 2, 
produced the largest yield of spears as measured by weight and the largest num- 
ber of spears over the seven-year period. 



34 BULLETIN No. 401 [April, 

Light Second-Year Cutting Superior to Third-Year Cutting 

The effects of starting the cutting of an asparagus plantation the 
second year after setting as compared with the third year are shown 
in Table 3 and Fig. 2. 

Cutting on Plots 2 and 4 started in 1928 and is designated thruout 
the discussion as second-year cutting. Plot 1 was not cut until the 
third year after setting (Table 2). 

Weight and Number of Spears. The plots most severely cut dur- 
ing the second and third years showed a permanent reduction in yield, 
as measured by both weight of spears and number of spears, compared 
with the plots cut more lightly during these years (Table 3 and Fig. 2). 

The weight of spears cut from Plot 2, which was cut heavier than 
Plots 1 and 4, was less after the fifth season than the weight of spears 
from either of the other two plots. Tho a higher number of spears 
was cut from Plot 2 than from Plots 1 and 4 for the first three years, 
owing to the longer period of cutting, after the third year Plots 1 and 
4 produced the highest yields. 

Plot 4, which was cut for only 2 weeks the second year, yielded a 
heavier total weight of spears and a larger total number than Plots 1 
and 2 for all seven years of the experiment. Plot 1, on which cutting 
was delayed until the third year, gave a lower number of spears than 
either of .the second-year cutting plots until after the fourth year of 
the experiment, when it exceeded Plot 2. 

An analysis of the total seven-year yields in pounds per plot shows 
that Plot 4, which received light second-year cutting, gave an increase 
of 22-percent over Plot 2, which received a heavy second-year cutting, 
and a 13-percent increase over Plot 1, which was not cut at all until 
the third year. 

Quality of Spears Reduced by Severe Cutting 

The market quality of all spears was influenced to a great extent 
by the various degrees of severity of cutting during the early life of 
the asparagus plantation. The size of spears, as indicated by individual 
weight and by diameter, decreased in direct proportion to the severity 
of cutting (Table 5 and Fig. 3). The figures represent the average 
performance of the six treatments for the seven-year period. 

All plots cut the first year (Plots 5, 3, and 6) gave the smallest 
proportion of No. 1 spears and the largest proportion of the lower 
grades. Heavy second-year cutting (Plot 2) gave lower quality of 
spears than third-year cutting ( Plot 1 ) ; while light second-year cutting 
(Plot 4) gave higher quality than third-year cutting (Plot 1). 



1934] 



ASPARAGUS YIELDS AS AFFECTED BY CUTTING 



35 



TABLE 5. EFFECT OF VARIOUS DEGREES OF CUTTING UPON MARKET QUALITY OF 
SPEARS HARVESTED DURING SEVEN-YEAR PERIOD" 



Plot 


Percent of total spears in each grade 


Average 
weight 
per spear 


Average 
diameter 
of spears 


Based on number 


Based on weight 


No. 1 


No. 2 


Strings 


No. 1 


No. 2 


Strings 


1 


45.8 

48.7 
42.8 

38.7 
38.0 
35.9 


39.6 

39.1 
41.4 

41.9 
41.6 
44.5 


14.6 

12.2 
15.8 

19.4 
20.4 
19.6 


69.6 

71.8 
68.8 

65.4 
64.0 
60.6 


27.4 

25.7 
28.1 

30.4 
31.1 
34.6 


3.0 

2.5 
3.1 

4.2 
4.9 
4.8 


gms. 
29 

30 
27 

24 
23 
22 


He inch 
7.28 

6.96 
6.51 

6.31 
6.05 
5.76 


4.. . 


2 


5... 


3 


6 





During the first two years all spears were measured, while during the last three years, a repre- 
sentative sample consisting of half the spears was measured on alternate harvest days. 




14253 
NUMBER 1 GRADE 



142536 
NUMBER 2 GRADE 



4253 
STRINGS 



FIG. 3. EFFECT OF DEGREE OF CUTTING ON NUMBER OF SPEARS IN EACH GRADE 

Severe cutting of asparagus early in the life of the plantation reduced the 
quality of spears as measured by grade. The six plots are arranged in the above 
graph in order of increasing severity of cutting. The percentage of No. 1 spears 
decreased with more severe cutting while the percentage of the two lower 
grades increased. 



Growth of Tops Permanently Stunted by Severe Cutting 

Prolonging the cutting season of asparagus, since it lessens the 
growing period of the tops and thus restricts the food supply that is 
manufactured in the top and stored in the fleshy roots, tends to reduce 
the yield the following season. In order to insure high yields of 
asparagus, a full growing season is necessary. 



36 



BULLETIN No. 401 



The effects of severe cutting upon the growth of tops were deter- 
mined by growth records and measurements taken in September, 1929, 
the third year of the experiment, and early in October, 1933, the 
seventh year (Table 6). Every third crown in each plot was taken as 
a representative sample. Each stalk was measured just above the 



TABLE 6. EFFECT OF VARIOUS DEGREES OF CUTTING UPON GROWTH OF TOPS 



Plot 


Height of stalk 


Average diameter 
of stalks 


Average number of 
stalks per crown 


1929 


1933 


Aver. 


1929 


1933 


Aver. 


1929 


1933 


Aver. 


1 


inches 
49.8 

51.5 
49.2 

45.3 
47.0 
42.9 


inches 
58.7 

59.8 
58.3 

59.5 

57.5 
57.5 


inches 
54.3 

55.6 
53.8 

52.4 
52.2 
50.2 


M inch 
5.13 

6.28 
5.17 

5.25 
4.85 
4.90 


Hs inch 
6.70 

7.10 
7.00 

7.20 
6.80 
6.80 


H-> inch 
5.93 

6.69 
6.09 

6.21 

5.84 
5.87 


6.9 

5.7 
6.0 

4.7 
5.3 
4.6 


9.8 

9.6 
8.6 

8.3 
8.3 
8.5 


8.35 

7.63 

7.27 

6.50 
6.80 
6.55 


4 


2 


5. . 


3 


6 





ground. Stalks, which were somewhat oval in cross-section, were 
measured thru the smallest diameter. Growth records showed that 
severe cutting restricted the growth of tops in 1929. The height of 
stalk, the number of stalks per crown, and average diameter of stalks 
were reduced somewhat in proportion to the severity of cutting. The 
results in 1933 were quite similar in that the most severe cutting during 
the early years of the plantation still showed up in reduced vigor of 
tops. 

The 1929 results indicate that severe cutting during the first three 
years of growth of an asparagus plantation retards the growth of tops 
at the end of the third year ; the records of 1933 show that this stunt- 
ing is permanent.