62 EXPERIMENT STATIO]Sr EECOKD. 



of the fruit-growing industry, it is considered a serious pest only in limited 

 areas in the San Francisco Bay district. Peach and apricot stocks are most 

 susceptible to attack ; the almond, cherry, apple, and native plums are less so ; 

 and the wild plum, known as the Myrobalan or cherry plum {Primus cerasif' 

 era), is almost entirely exempt except when a tree has been weakened by some 

 cause, such as lack of water or cultivation or when it has been partly killed by 

 " gophers " or other rodents. Almond stocks are more or less resistant if planted 

 in soils suitable to their growth. 



Borers appear to attack trees more readily when they are planted in soils of 

 a light, sandy, or gravelly texture. The author does not believe that newly 

 hatched larvas can reach the lower crowns or roots more easily in light than in 

 the heavy soils of loam or clay ; it appears rather, that the trees themselves 

 are not so strong and are therefore not so resistant. 



Life-history studies and investigations of methods of control, here reported 

 in detail, are summarized as follows: "Adult moths are flying from June to 

 and including September, and are present in maximum numbers during July 

 and August. As they place their eggs immediately after emerging, the period 

 of oviposition conforms with that of the flight of the moths. The egg stage 

 lasts about 2 weeks, so that the period when the newly hatched larvfe are 

 entering the tree is about from the middle of June to the middle of October. 

 The period when they are entering in maximum numbers is from the middle of 

 July to the middle of September. Any repellent or protective wash, therefore, 

 should be applied before the middle of Juna Worming should be practiced 

 during the winter or early spring months, and it is very important that only 

 sharp tools be used. The bark should be cut and not broken from the tree, 

 and so far as possible only dead bark should be cut away. The most effective 

 wash that can be used in conjunction with the worming method is considered 

 to be the lime-crude oil formula No. 1. Heavy crude oil is thought to be re- 

 pellent to the borer moth and acts to draw many of the worms out, but it is 

 extremely injurious to some trees. It is apparently safe when combined with 

 lime. Such preparations as residuum oil, gas tar, or asphaltum can be ap- 

 plied directly to the bark of the tree with only a little danger, but common 

 practice has demonstrated that a combination with lime is almost as efficient 

 and far safer than the crude oil alone." The lime-crude oil mixture is made 

 as follows : Place about 50 lbs. of rock lime in a barrel and slake with 10 or 15 

 gal. of warm water; while the lime is boiling, slowly pour in 6 or S gal. of 

 heavy crude oil and stir thoroughly. Add enough water to make the whole a 

 heavy paste. It should be applied immediately with, a heavy brush. 



A list of 21 references is appended. 



Cotton leaf -worm, and how to control it, P. Hayhuest {Farm and Ranch, 

 SO (1911), No. ^0, p. 11). — This pest is reported to have been unusually 

 abundant in Arkansas in 1911, causing the greatest injury in the eastern half 

 of the State, particularly in sections along the Arkansas River from Russell- 

 ville and southward. It even occurred in destructive numbers in Randolph 

 and Clay counties in the extreme northeast. 



Bee keeping' in Porto Rico, W. V. Toweb {Porto Rico St a. Circ. 13, pp. 31, 

 fig. 1). — The author states that at the present time the honey industry of 

 Porto Rico is in its infancy, there being but few apiaries on the island ; these 

 are largely located in the mountainous district of Ponce and in Mayaguez. 

 " The northern, western, eastern, and interior portions of the island are excep- 

 tionally well adapted to the bee industry, while the south side is not considered 

 so good on account of the scarcity of rain during all seasons of the year. The 

 bees at the experiment station have never had to be fed during the winter 

 months of the year. This year 2 hives of Italian bees have been weighed 



