THE MONTHLY BULLETIN. 555 



THE CORN WORM. 



{Hellothis oisoleta Hiibn.) 

 Ordei — Lepidoptera. Family — Noctuidse. 



By A. J. Cook, State Commissioner of Horticulture, Sacramiento, Cal. 



The corn worm, often known as corn-ear worm, less frequently as 

 tomato worm, and again as cotton-boll worm [Heliothis ohsoJeta), is 

 a serious pest in all parts of California. The moth lays the ribbed egg 

 in spring. The pink, often darker, caterpillar — "worm" — enters at 

 the silk end of the ear, and feeds on the growing kernels, causing 

 pronounced furrows, and soiling the ear with its repulsive excrement. 

 It feeds for near a month and reaches one and one half inches in length, 

 when it enters the earth and pupates in an earthen cocoon, lined 

 loosely with fine silk. The pupa is green at first, but soon becomes a 

 bright brown. The moth which comes in a short time, in case of the 

 summer brood, from the pupa varies in color and markings. It is 

 generally yellowish or grayish and expands nearly two inches. Unlike 

 most moths of the family NoctuicUe, it flies by day. There is a summer 

 and an autumn brood. 



As suggested in the common names, it feeds on the cotton-boll, the 

 corn ears and the tomato fruits, though it eats sparingly of the leaves 

 and stems, into which it bores. It is partial to corn, especially sweet 

 corn, hence a remedy for the tomato gardener: By planting rows of 

 sweet corn among the tomatoes, every tenth row should be corn, the 

 moth is attracted from the less inviting tomato plants. The fondness 

 of this insect for sweet corn attracts it to this plant, and the tomatoes 

 escape. By dusting the silk of the corn with lead arsenate, or spraying 

 with the same in water, two pounds to fifty gallons, we poison the 

 caterpillar and save the corn. I have known the corn to be saved by 

 careful hand picking. This in the garden, in a small way, is quite 

 satisfactory. 



NEMATODE WORMS AND MOTTLED LEAF. 



By J. R. Hodges, Horticultural Inspector, Covina, Cal. 



Having obtained consent of Mr. A. R. Meserve over a year ago to 

 make an investigation of mottled leaf of citrus trees, I commenced 

 making a careful microscopic examination of the leaves, branches, bark, 

 wood and finally the soil and roots of diseased trees. My examination 

 was largely confined to trees badly enough affected with mottled leaf 

 as to interfere with the proper ripening of the fruit, making what is 

 called "small offs" in the packing-house. After examining a great 

 many trees on different kinds of soil, I noticed that there was one 

 condition common to all trees badly affected with mottled leaf: an 

 imperfect condition in the fibrous root system, sometimes amounting to 

 a great scarcity of fibrous roots which were broken down, scarred and 

 in various stages of decay. At first I found, under the microscope, 

 only parts of the nematodes, a head here and a tail there, but later' 

 by scraping the rootlets while submerged in water, I found live' 

 actively moving specimens, in many cases very numerous on badly 

 decayed roots. I have obtained as many as fifty specimens from four 



