THE MONTHLY BULLETIN. 215 



The Cherry and Pear Slug. 



Tlie pear slug is the young of an insect whieli belongs to the same 

 order as the honeybee. We know the slug as a dark, olive-green, slimy 

 worm with the anterior portion enlarged. It strips the upper green 

 surface of the leaves which later turn brown. This pest feeds on the 

 })ear, cherry, plum, quince, etc., and it is very easy to control by blowing 

 lime and dust upon the infested leaves, or by spraying with the ordinary' 

 soap and emulsion sprays; also arsenate of lead, four pounds to 100 

 gallons of water. The latter spray is slow in action as the slugs must 

 ('(it the j)oisou to be destroyed. 



CITRUS FRUIT INSECTS. 



Plant Lice. 



Plant lice are also injurious to citrus trees. The black citrus plant 

 lice are probably the most common of the aphids on this host. They 

 will be found principally on the most tender growth on which they may 

 <lo much damage. Curled leaves result from their attack and serve as a 

 forceful indication of their presence. The black-leaf .spray recom- 

 mended above will do etlficient Avork if applied properly. A Braconid 

 Wy parasite is controlling these aphids absolutely, in many of the groves 

 of Sacramento and Placer counties. — A. J. Cook. 



The Citrus Red Spider. 



The red spiders are minute web-spinning reddish mites with eight 

 legs. They are generally found on the under surface of the leaves and 

 produce a spotted eifect. Dry flowers of sulphur blown on the trees 

 may be used, or the commercial lime-sulphur solution diluted to 2 or 

 2^ per cent. This latter arachnicide is replacing the flowers of sulphur. 

 Use a fine misty spray with strong pressure. Apply spray when mites 

 are numerous. 



Orange Thrips. 



The orange thrips are minute active brownish or j^ellowish insects 

 which are so common in the orange blossoms on the leaves and tender 

 foliage. There are several species which produce different effects on 

 the host : one causes a leathery distorted growth to the leaves and 

 marks the fruit in the form of a ring around the stem end or down in 

 streaks. Another thrips produces a mottled pale color in the leaves 

 and causes the surface of the fruit to turn silvery. Other species 

 attack the parts of the flower. The spray recommended by the United 

 States Bureau of Entomology consists of commercial lime-sulphur 33" 

 Baume, 2^ gallons; black-leaf extract, 2 gallons of 2 J per cent, or 1-t 

 fluid ounces of 40 per cent; water 200 gallons. Always maintain as 

 strong a pressure as is possible. It may. become necessary to make 

 several applications, the first being applied usually just after most of 

 the petals have fallen; the second, ten to fourteen days after the first, 

 and the third, three to four weeks after the second. 



