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insects sometimes cause severe damage to sugar orchards. Rem- 

 edy : spray about May 15 with arsenate of lead, 3 pounds to 50 

 gallons of water. 



Canker Worms. 



These insects of two similar species are true loopers or inch 

 worms. Eggs : laid in small masses on bark of infested trees in 

 fall or spring. Larva : generally dark colored, with variable faint 

 yellowish stripes. The feeding period extends from May 1 to 

 about June 20, badly infested trees appearing as if swept by fire. 

 Pupa : formed in an earthen cell at variable depth in the ground. 

 Moth : ashy gray in case of male, dull gray in case of female 

 which is wingless, and is obliged to crawl up the tree in order to 

 deposit her eggs. Remedies : banding the trees with sticky mate- 

 rials in November will intercept the female moths of the fall 

 species. The same treatment repeated in March and April will 

 prevent the ascent of the spring canker worm. Spraying about 

 May 15 with arsenate of lead, 3 pounds to 50 gallons of water, 

 is also an effective remedy. 



Plant Lice. 



These insects feed on plant juices, and are best combated by 

 spraying with kerosene emulsion, 1 part to 9 of water, or with 

 whale oil soap, 1 pound to 8 gallons of water. The elm leaf louse 

 curls the terminal leaves of elm twigs early in the spring. A like 

 effect is produced on the apple by the common green aphis, and 

 the cherry and peach are afflicted by a plant louse of similar 

 habits. The important thing in treating these insects is to drive 

 the spray forcibly into the curled leaves, and to make a second 

 treatment about one week after the first spraying. 'With plant 

 lice it is a general rule that by midsummer their natural enemies 

 develop in sufficient numbers to check their increase. 



Spiny Elm Caterpillar (Vanessa). 



Eggs : laid early in the spring in a band around twigs of elm, 

 willow or poplar. Larva : the dark colored spiny caterpillars feed 

 in clusters, and commonly strip one or more branches by June 25 

 at about which date they descend the trees to transform. Occa- 

 sionally an entire tree is defoliated. Pupa: dull grayish, armed 

 with short spines; usually found under fences and in sheltered 

 places. Butterfly: expands 2|- inches, very dark brown with a 

 conspicuous yellow border. The second brood of caterpillars 

 appears in August, and the butterflies winter under bark, in 



