textured Barnes loam soil, level topography, 
and water tables well below 10 feet. 
Cultivation treatments were designed as 
follows: complete — sod removal between 
tree rows and between the trees in the row; 
moderate — sod removal between tree rows 
only; light — sod removal between tree rows 
but about half the width of the moderate 
treatment; check — no sod removal. About 
20 trees of each species were included in each 
treatment. Treatments were arranged in a 
randomized block design with two replications 
in each belt. 
Cultivation was initiated in July 1960. 
Complete, moderate, and light treatments 
were mowed, cultivated with a rototiller, and 
then disked. Mowing was necessary to pre- 
vent clogging of the tiller blades. All imple- 
TABLE 1. — Two-year growth averages after culti- 
vation — Westhope area planting 
Species Height Diameter an 
(Row ) ( Feet ) (Inches ) ( Feet ) 
Complete Cultivation 
Caragana ga 1 — 
Rocky Mtn. juniper 1.53 0.44 ap a: 
American elm* 1.89 0.44 0.70 
Boxelder 1.44 0.26 0.56 
Caragana? 0.88 — — 
Moderate Cultivation 
Caragana 0.50 — — 
Rocky Mtn. juniper 1.56 0.44 1.16 
American elm* 1.86 0.49 1.03 
Boxelder 1.36 0.29 0.66 
Caragana? 0.74 — — 
Light Cultivation 
Caragana 0.89 — — 
Rocky Mtn. juniper 1.37 0.41 1.09 
American elm* 1.47 0.37 0.02 
Boxelder 0.85 0.29 --0.07 
Caragana? 0.86 — —_ 
Check 
Caragana 0.51 — — 
Rocky Mtn. juniper 1.34 0.33 0.99 
American elm 0.60 0.22 --0.52 
Boxelder 0.68 0.22 --0.06 
Caragana? 0.57 a — 
* Cultivation treatments significantly different (5- 
percent level) from check. 
1 A dash (—) means no measurements taken. 
2 This row was a mixture of caragana and choke- 
cherry; only the caragana was measured. 
ments were tractor-drawn, except a small 
gasoline-powered roto-tiller used for cultiva- 
tion around trees in the complete treatment. 
The check was left undisturbed. 
During subsequent cultivations in 1961 
and 1962 the work was accomplished with a 
tractor-drawn field cultivator and tandem 
disk. The distance between rows in both belts 
was approximately 10 feet, which was suf- 
ficient to allow passage of tractor and imple- 
ments. The number of cultivation operations 
necessary during a season varied, of course, 
with weather conditions. During dry years 
such as 1960 and 1961, with precipitation 
totals of 11.74 and 8.24 inches respectively, 
two or three operations were sufficient. With 
more favorable temperatures and precipita- 
tion, additional cultivations might be neces- 
sary. 
Height, diameter, and crown spread were 
the three measurements of treatment effects. 
Height and crown spread were measured to 
TABLE 2. — Two-year growth averages after culti- 
vation — Souris area planting! 
: A Z Crown 
Species Height Diameter spread 
(Row ) ( Feet ) (Inches ) ( Feet ) 
Complete Cultivation 
Caragana 73 2 — 
Boxelder 1.64 0.35 1.34 
Green ash 2.02 0.56 1.74 
Caragana 1.53 — — 
Moderate Cultivation 
Caragana 0.63 — — 
Boxelder 1.97 0.44 1.68 
Green ash 2.11 0.59 2.09 
Caragana 1.76 — — 
Light Cultivation 
Caragana 0.59 — — 
Boxelder 1.74 0.36 1.06 
Green ash 1.70 0.54 0.93 
Caragana 1.37 — — 
Check 
Caragana 0.25 — — 
Boxelder 0.03 0.15 --0.38 
Green ash 0.13 0.16 0.05 
Caragana 0.54 — 
1 All cultivation treatments significantly different 
(d-percent level) from check. 
2 A dash (—) means no measurements taken. 
