MISC. PUBLICATION 303, U. S. DEPT. OF AGRICULTURE 
other species, but this should be done most carefully. If the proper 
species for the required job are lacking, the planting should be par- 
tially or entirely deferred until the next season. 
PLANTING FOE WILDLIFE 
In planting for wildlife the aun is * * the creation of such 
an environment that the maximum of food and cover is available at 
all seasons of the year for the particular birds or mammals consid- 
ered" {1S8^ p. 16). It f ollovrs that considerable care is called for in 
the selection of proper plant species. This is not a simple matter. 
Many species may be adapted for planting in a given area. Discard- 
ing those that are of little value in the control of erosion, we are left 
with a list of plants that have diverse values as food for wildlife. 
To date, recommendations of a species for planting have rested 
upon the utilization of its fruit by birds or mammals. There is a 
difference between the unportance of a certain item of food in the diet 
of a given bird and the value of a species of plant for wildlife in 
general. The one relates to the welfare of a particular species of bird, 
the other to the extent to which a plant is used by mammals as well 
as various species of birds. Wh.en the welfare of wildlife in general 
is to be considered we can scarcely limit our choice to a species of 
importance to the bobwhite alone, for example, although such use 
will naturally influence our choice. Furthermore, we can scarcely 
ignore other forms of wildlife even if we wish to encourage the pro- 
duction of only one. 
McAtee {369) has said the- importance of food items in the diet 
of a bird is not indicated by statements as to the frequency with which 
the items are taken. It is only under the percentage-by-bulk system 
(the proportion of one food taken to the total amount of all foods 
taken) combined with the counting of individuals, insofar as this is 
possible, that the nearest approximation to the truth can be made. 
Under the percentage-by-bulk system, he explains, comparison of 
one part of the diet with another or of the food of one species or 
group of species with that of another is possible. 
But he goes on to say {369^ p, 4^-^)5 * * statements of the 
frequency of occurrence of food items in bird stomachs may perhaps 
be taken as rough indices of availability of the food or relish for it." 
And in the publications so well known to biologists engaged in wild- 
life management, he employs as his criterion of use the number of 
birds known to have eaten the fruits, buds, catkins, or other parts. 
Examination of the record of the species of plants listed in this 
publication will show some to have been utilized by a great many 
species of birds and mammals. Such species should undoubtedly be 
given priority in making planting lists. Other species may have very 
poor records. This may be true often because they are actually not 
used by wildlife. On the other hand, they may occur in a region 
from which only a few bird stomachs have been examined. They 
may bear fruits difficult to identify by ordinary methods of stomach 
analysis. The fleshy fruit of Prunus americana, for instance, has been 
found only once, in the stomach of a pine grosbeak, but observers have 
noted that many birds eat this fruit. 
