INTRODUCTION 
The effects of elevation and of aridity are important in con- 
trolling distribution of native plants in the Southwestern States. 
Recommendations of the most widely distributed species are made with 
the assumption that the favoring influences of cultivation will 
enable plants to survive outside of their native environment. The 
extralimital species listed have of course been tested and their 
hardiness under the prevailing conditions demonstrated. 
Table 1 shows groups of fleshy fruits most attractive to 
birds throughout the United States and lists desirable kinds of 
birds most fond of the fruit. No barberries, currants, or buckthorns 
are listed, because they harbor rusts destructive to plants of eco- 
notic importance. Junipers are in almost the same category, as they 
serve as alternate hosts for apple rust, but there is no reason why 
they cannot be used in districts where apples are not commercially 
grom, as they are among the most valuable plants for wildlife. 
Snitted also are plants poisonous to man on contact, as poison ivy 
and poison sumac, as well as various kinds dangerously poisonous to 
domestic animals, as yews, wild cherries, and nightshades, in spite 
of the fact that wild cherries are greatly rclisned by birds. Brows- 
ing animals are known to have been killed by feeding on the leaves 
of wild cherries but do not seem to be so seriously affected by 
those of plums. Certain plants included among fleshy fruit bearers 
in previous publications have been transferred to the list of seed 
producers, hence do not appear in the present series of leaflets. 
These include magnolia (Magnolia), bittersweet (Celastrus), and 
burningbush (Euonymus). 
It should be noted that the fruit-bearing seasons recorded, 
being collected from varied sources, tend to be maxima. As a rule 
they are not likely to be realized or even approached in a single 
locality unless numerous specimens of a given species are present 
and so distributed in sun and shade as to favor both early and 
late fruiting. 
The word "extralimital" as here used in certain table head- 
ings covers plants from other States or regions of the United States 
as well as wholly introduced, exotic, or foreign plants. 
