1690 



ENCYCLOPEDIA OP PRACTICAL HORTICULTURE 



food. If it touches a plant louse it im- 

 mediately raises it into the air and sucks 

 it dry. This is very rapidly repeated 

 with very disastrous results to the lice. 

 When the larva is full grown it seeks 

 some sheltered spot in which to pupate. 



The adults are very swift fliers and are 

 often mistaken for bees. They are com- 

 mon around flowers, feeding upon the 

 nectar and from this habit get the names 

 "flower or honey flies." They are some- 

 times called *'sweat flies" in the Eastern 

 states. Their eggs are deposited singly 

 upon leaves and twigs which are infest- 

 ed with plant lice. 



Among the more familiar species of 

 syrphus flies are the following: Lasioph- 

 tnicus pyrastri Linn. This is one of the 

 largest species. It has a yellow face with 

 eyes dark red to brown, thorax irridescent 

 green or blue, abdomen velvety black. 

 Widely distributed. 



Syrphus americanus Wied. 



Somewhat smaller than L. pyrastri, 

 though similar in form and color, except 

 that the abdomen has three broken bands 

 of yellow along the sides. Reported from 

 nearly every section of the country. 

 AUograpta oMiqua Say. 



This species is only a quarter of an 

 inch in length. The body is dark and 

 very slender. Eyes dark red. Pace yel- 

 low. Thorax irridescent green. Abdo- 

 men dark with four transverse yellow 

 bands on the back and yellow markings 

 at the base of the ovipositor. Not so 

 widely distributed as the others. 



Internal Parasites 

 *Ichneiimoii Fly, Chalcis and Ensign Flies 



A membranous winged insect of the 

 same general family as the bee, wasp and 

 ant, parasitic on various pests such as 

 aphids and certain kinds of caterpillars. 

 The females of some species are supplied 

 with sharp ovipositors with which they 

 puncture the body walls of their victims, 

 laying their eggs within the living tissues, 

 where larvae hatch and feed, causing the 

 death of the host. Sometimes the eggs 

 are laid on the outside of a caterpillar, 

 and f hen the larva hatches he bores his 

 way down into his host 



*For technical description see California Hor- 

 ticultural Commission, Vol. 1, No. 7. 



The enemy of the aphid is one of the 

 smaller ichneumons. It punctures the 

 louse with its sharp ovipositor and lays 

 its eggs. When the grub hatches it feeds 

 upon the body of the aphid until the lat- 

 ter dies, when it slits a hole in the under 

 wall and glues the mummy to the leaf 

 with a sticky substance. It then uses 

 the body wall of the aphid for a pupa 

 case and undergoes its transformation, 

 and when ready to emerge cuts a round 

 hole in the upper side and makes its es- 

 cape a full-grown fly, ready to do more 

 damage in the plant-louse world. 



Iclinenmon Fly 



The infested lice may be recognized 

 by the inflated appearance while the 

 bleached mummies still adhering to the 

 leaves and stems of aphid-infested plants 

 are mute witnesses to the effectiveness of 

 their parasitic enemy. 



There are several species, and widely 

 distributed. 



Chalcis Fly 



These flies, of which there are several 

 species, are mostly minute insects, usual- 

 ly black with a metallic luster, though 

 some are yellow. 



These flies prey upon many varieties 

 of insect pests, scales, aphids, caterpillars 

 and various larvae such as those of the 

 cabbage butterfly. Por the most part 

 eggs are laid within the body of the 

 food insect, where the young larvae de- 

 velop at the expense of the host. 



PLANTING TABLE 

 Usual Distances Apart for Planting Frnits 



Apples 30 to 40 feet each way. 



Apples, dwarf 10 to 15 feet each way. 



Pears 20 to 30 feet each way. 



Pears, dwarf 10 to 15 feet each way. 



Plums .. .16 to 20 feet each way. 



Peaches 16 to 20 feet each way. 



Cherries 16 to 25 feet each way. 



Apricots .. 16 to 20 feet each way. 



Nectarines 16 to 20 feet each way. 



Quinces 8 to 14 feet each way. 



Figs 20 to 25 feet each way. 



Mulberries 25 to 30 feet each way. 



Japanese persimmons 20 to 25 feet each way. 



Loquats 15 to 25 feet each way. 



Pecans 35 to 40 feet each way. 



Grapes 8 to 12 feet each way. 



Currants 4x5 feet. 



Gooseberries 4x5 feet. 



Raspberries, black 3x6 feet. 



Raspberries, red 3x5 feet. 



Blackberries 4x7 to 6x8 feet. 



Cranberries 1 or 2 feet apart each way. 



Strawberries 1 x 3 or 4 feet. 



Oranges and lemons 25 to 30 feet each way. 



