In southern Idaho, tall bitterbrush was 
topped 3 feet above the ground. Initial re- 
sponse was spectacular; however, the ratio of 
production between topped and control shrubs 
dropped steadily from about 9:1 in the first 
growing season to about 2:1 in the fourth sea- 
son after topping (Ferguson and Basile, 1966). 
A major benefit of the topping is the nearly 
complete availability of the new growth. Be- 
fore treatment, practically all new growth was 
beyond the reach of deer. Further research is 
needed to determine if treatment as severe as 
this affects longevity of the plants and if re- 
peated removal of twig growth stimulated by 
pruning will maintain the increased production 
at a higher level. 
Hinge-cutting of trees and tall shrubs bene- 
fits browsing animals. Under this practice, 
trees and tall shrubs are partially cut above 
the ground and are tipped over so that the tops 
are accessible for use. The partial or hinge cut 
permits the fallen tree to remain alive and put 
on new growth, all of which is accessible to 
browsing animals. The foliage in treetops that 
receives full sunlight is commonly more palat- 
able and nutritious than lower parts. This ob- 
servation is confirmed by Hoffman (1961) in 
his studies of winter forage of blue grouse. The 
partial cut also stimulates production of basal 
sprouts. 
Hinge-cutting as a habitat improvement 
practice is more widely used in the Northeast- 
ern States, often in connection with wildlife 
clearings. 
Prescribed Burning—Some of the earliest 
work in prescribed burning was the evaluation 
of bobwhite quail production in relation to 
burned-over range (Stoddard 1942). The time 
of burning determined whether quail habitat 
would be improved or damaged. Unless late- 
winter burning was done prior to the end of 
February, newly sprouted legume food plants 
were greatly harmed. 
In the South, burning removes both the old 
herbage of broom sedge and the accumulation 
of litter. It stimulates a succulent growth of 
various perennial legumes that are important 
in the quail’s diet. Winter berries and fruits 
are also important food items. To prevent 
widespread loss of these important foods, a 
system of fire lanes may be needed to provide 
fire protection for some of the more productive 
berry-producing areas. 
Field tests have also demonstrated the im- 
portance of prescribed burning on certain deer 
ranges. In western Oregon, a comparison of 
cutover and burned openings with check areas 
in untreated timbered range showed significant 
differences in deer production (Einarsen 
1946). Harvested bucks on the burned range 
averaged 213 pounds. On the closed canopy 
28 
range, bucks averaged 125 pounds. The protein 
content of preferred browse was consistently 
higher on the burned range than on the tim- 
bered range. Weight losses and mortality coin- 
cided with periods of low protein levels, which 
were more pronounced during extended periods 
of cloudy weather. 
In Arizona chaparral types, protein content 
of browse in recent burns was found to be gen- 
erally higher than that in unburned areas 
(Swank 1958). Browse use by both deer and 
cattle was much greater in the burn than on 
adjacent range. The favorable effects of burn- 
ing were significant for 1 or 2 years, but de- 
clined in succeeding years. In California, 
Schultz et al. (1958) found that prescribed 
burning increased the nitrogen and phosphorus 
available to plants. Under favorable burning 
conditions, dense chaparral can be effectively 
controlled by prescribed burning; however, 
there is a risk that the fire may burn beyond 
control. 
Fertilizing —To improve wildlife habitat, 
the application of fertilizer to wildlife range 
has not been adequately tested. To date field 
tests have been sporadic and not completely 
coordinated. One of the principal drawbacks to 
this practice is its moderately high cost and 
the need for periodic followup treatments. 
Washington State perhaps pioneered the 
large-scale use of fertilizers as a result of 
public pressures to divert elk use from private 
farmlands on the Olympic Penninsula. Start- 
ing in 1954, various fertilization trials led to 
the practice of applying 2 tons of oyster shell 
aggregate lime and 160 pounds of 10-20-20 
chemical fertilizer per acre on nearby State- 
owned lands. When planting accompanies fer- 
tilization, the treated forage attracts elk 
throughout the summer, fall, and winter. On 
established sod, fertilizer is added in Septem- 
ber, and elk are held throughout the following 
winter (Brown and Mandery 1962). Treatment 
every year or two is needed because of the high 
annual precipitation and its leaching effect. 
In California, brush seedlings responded to 
fertilizers, but at different degrees than 
grasses (Schultz et al. 1958). It was found that 
composition could be changed by different ap- 
plications of fertilizers and that one browse 
species could be favored over another by dif- 
ferential treatment. The sugar content of 
plants was raised by the application of phos- 
phorus and potassium, whereas nitrogen pro- 
longed succulence of plants. 
Two soils derived from basalt and pumice 
and supporting bitterbrush were given fertil- 
izer treatments to test forage response in east- 
ern California (Wagle and Vlamis 1961). Bit- 
terbrush plants in the basaltic soils formed 
root nodules and apparently had an adequate 
