56 



ANNUAL REPORT 1918 AND 1919 



Hillside lands run great risk from wash in heavy rains. At any 

 point where water is liable to congregate some run-off must be provided 

 and cement or other pipe so placed that a slide may be unlikely. In this 

 connection alfalfa, lippia or some other growth with roots which have a 

 tendency to hold the soil will be advantageous. At this point it may be 

 well to say that a good supply of lima bean straw as a mulch is exceedingly 

 useful on the terraces in case of heavy rains in helping to control the unruly 

 rush of storm waters. Not only this, but the mulch will act as a saver 

 of irrigating water by preventing evaporation of moisture, it will obviate 

 the necessity of much cultivation, prevent the growth of noxious weeds, and 

 finally by its decay will provide the humus and nitrogen so necessary for 

 the replenishment of the soil, which will naturally be exhausted by such 

 vigorous feeders as producing avocado trees. 



The care of hillside planting is more expensive than that of level or 

 nearly level ground and because of the inability to plow up and down 

 the hill, more hand work is necessary. In order to obviate this last, I am 

 experimenting in making small terraces between the larger ones, which can 

 be cultivated lengthwise with facility and which will allow the growth of 

 cover and other crops while the trees are young. A friend of Mr. Sallmon, 

 Mr. R. C. Allen, has made a hillside planting by leveling a circle wherever 

 he desires to plant a tree. This basin he filled with mulch and irrigates 

 from above, giving no other care. With a very large supply of bean 

 straw, this might be done on terraces and the slight cultivation now 

 necessary after irrigation be largely avoided. 



The protection against frost afforded by many hillsides is very con- 

 siderable, the thermometer readings varying as much as six degrees on cold, 

 calm nights, where the points of observation differ about 125 feet in 

 elevation. In this connection I may say that the cost of the terraces and 

 the greater expense of cultivating the trees on a hillside, if any, should be 

 looked upon as an insurance against frost, which it is to a very considerable 

 degree, in my opinion. 



OBSERVATION ON FROST INJURY TO AVOCADOS 



By C. F. Kinman, U. S. Department of Agriculture 



In looking over the frost injury evidence in this part of the state, I 

 was pleased to find the avocado orchards in better condition that I had 

 expected they would be, and the same is true of many other sections of 

 the state. The point that impressed me most forcibly was that during the 

 past severe winter the behavior of difFerent varieties in different localities 

 and of individual trees of the same variety in a given orchard has been 

 decidedly varied. One must be exceedingly careful in his observations and 

 considerate in his praise or condemnation of any given variety. The evi- 

 dence as found in a given locality or orchard was certainly not sufficient 

 for a stranger in that orchard or locality to rate a variety or individual 

 tree as so much depended upon the local conditions and the treatment that 

 had been given. 



The vigor of the tree, it appears to me, has been the principal condi- 

 tion upon which depended its inability to withstand cold, and only after 



