424 



prepared as follows : 10 lb. of black soap is dissolved in 4-5 gals, of 

 hot water and 2 lb. of sodium carbonate is dissolved in 1 gal. of 

 water ; the two solutions are mixed and 1 gal. of spirit, 2 gals. 

 of tobacco extract and 95 gals, of water are added. The adults 

 can. arlsp be collected with the Haltica funnel. Arsenicals may alsa 

 be used against these beetles. These control measures may be applied 

 against Galeruca (Galerucella) capreae and Galerucella Uneola., as well as- 

 against Plagiodera armoraciae and various species of Haltica. „j^ 



Hymenoptera : — The larvae of Cimbex, Hylotoma, and of many species, 

 of Nemaius feed on the leaves of the willow ; those of other Nematus- 

 hve wdthin the leaf-galls produced by them, while Sirex larvae live in 

 the wood like Longicorn larvae. The larvae of Pontania and many of 

 those of Cryptocampa live in the petioles and in the buds, causing- 

 various malformations. The controls given above may be used 

 agaipst all these pests. 



Lepidoptera : — The larvae of Pieris rapae, Apatura ilia, Vanessa- 

 polychloros, V. antiopa, Sphinx {Smerinthus) ocellata and Amorpha 

 {S.) populi occur on the willow, but do not do noticeable injury. The 

 larva of Aegeria (Sesia) apiformis mines the trunks of willows and 

 poplars and requires the same treatment as Longicorn larvae. 

 Collection and destruction of infested t^^^gs is the control advised in 

 the case of Aegeria {Sesia) formicaeformis. The larva of Earias 

 clilorana binds the terminal leaves in a bundle, within which it devours 

 the bud and stem. The nymphal stage is passed in a cocoon 

 on the branches. The leaf-bundles should be gathered and burnt before 

 the larva emerges. The wood-eating larvae of Cossus cossiis {ligni- 

 perda) and Zeuzera pyrina (aescidi) attack willows, the former the 

 trunk and the latter the branches. Lymantria dispar, Euprodis 

 chrysorrJwea and Stilpnotia salicis injure willows and should be 

 controlled by means of Ught traps and by scraping ofi the eggs, which 

 may also be painted over with tar. The larva of Dicr'anura vinitla 

 also occurs on the willow, as well as various Noctuids, Geometrids. 

 and Microlepidoptera. 



Rhynchota : — ^Various Cercopids, Aphrophorids and Tettigonids- 

 suck the sap and may be destroyed by repeatedly spraying with a. 

 2 per cent, black soap solution, or mth a solution containing 2 per cent, 

 black soap and 2 per cent, nicotine. These sprays are also effective 

 against Aphis saliceti and Melanoxajitherium (Melanoxanthus) salicis ; 

 and with the addition of 2 lb. of sodium carbonate and 1 gal. of spirit 

 per 100 gals, of insecticide, these solutions are useful against 

 Kermes salicis. 



Dipt era : — Rhabdophaga rosaria and R. pulvini are two Cecidomyids. 

 which injure willows. The larva of the former hves in a kind of gaU 

 at the tip of the branches, while that of the latter causes the youug^ 

 twigs to wither ; these must be cut off and burnt. ;, i ,.. i; .-/ 



Several species of Eriophyes (Phytoptus) attack the leaves and the 

 twigs of wallows and may at times do important damage. These mites, 

 may be controlled by cutting and burning infested material and by 

 using nicotine sprays. u-jvyiioi A>'~i'\<',^tu\u^"-\ iu- 



