Arizona x\gricultural Expkrimunt Station 27Z 



stronger sunlight and aridity, and also the quick shade which they 

 supply. The following species were recommended for planting over 

 the State : tive-leaf ivy or Virginia creeper (Parthenocissus vitacea var. 

 macrophylla) ; Japanese ivy (Parthenocissus tricuspidata) ; Japanese 

 honeysuckle (Loiiicera jdponica) ; English ivy (Hedera helix) ; Arizona 

 grape (Vitis arizonica) ; trumpet honeysuckle (Lonicera sempervirens) ; 

 silk vine (Pcriploca graeca) ; Chinese wistaria (Wistaria chiensis)/, 

 Chinese trumpet creeper (Tecoma chiensis) ; blue passion flower (Passi- 

 flora cacriilea) ; Japanese virgin's bower (Clcmatic paniculata) ; west- 

 ern virgin's bower (Clematis ligiisticifolia;) native hop vine (Humulus 

 lupuliis var. ncomexicana). 



Timely Hint No. 118, Crown Gall, deals with the well-known 

 disease of orchard trees and suggests means for its control. Severe 

 losses have resulted to Arizona orchardists from crown gall, and it may 

 be looked for now in practically every agricultural community in the 

 State. Recent studies have shown that in addition to deciduous fruit 

 trees, hops, grapes and cane fruits, crown gall attacks roses, chrysanthe- 

 mums,. Paris daisies, walnuts, white poplars and similar shade trees be- 

 sides field crops like sugar beets and occasionally alfalfa. Nurseries 

 have played an important part, often unconsciously, in the spread of 

 this disease. In the light of better information concerning the infec- 

 tious nature of crown gall, and with stringent state inspection laws, 

 there will be less danger than heretofore of introducing crown gall in 

 one's orchard. However, the orchardist and farmer should exercise 

 great care in purchasing nursery stock and insist that it be inspected 

 properly by the state authorities. 



STUDIES IN THE FLORA 



This department is assisting the forest service in this State to 

 identify the more important plants, both woody and forage species, that 

 grow on our forest areas. It is also cooperating in a like manner with 

 the Bureau of Biological Survey, Washington, D. C, relative to their 

 work of mapping the life zones of Arizona. More than 200 plants 

 were determined for the Coconino National Forest last summer and 

 smaller lots for other of the forest areas. Thus far 180 species have 

 been identified for the government biological survey work. Most of 

 these plant specimens are deposited ultimately in the herbarium of the 

 University for future reference. This work requires a considerable 

 outlay of time, but it is invaluable since it enables the Botanist to be- 

 come better acquainted with plants from widely separated localities in 

 the State and their distribution. It also helps to make more nearly 



