February, 191 1 



THE CANADIAN HORTICULTURIST 



37 



Growing Tomatoei iB the Greenhouse at McDoaaU College 



(See article on page X.) 



Insects That Attack Vegetables 



L. Caesar, B. S. A., O. A. C, Guelph, Ont. 



ROOT maggots are almost a cause of 

 despair to vegetable growers and to 

 entomologists. About one hundred 

 different kinds of remedies have been care- 

 fully tried against them, and only a few 

 of these found valuable, in fact I know of 

 no really satisfactory and economical 

 remedy for these insects. There are three 

 different kinds of root-maggots, though 

 they all look very much alike. The first, 

 Pegomva brassicae, attacks cabbage, 

 cauliflower, turnips, radishes and certain 

 closely allied wild plants like hedge mus- 

 tard and cress. The second, Pegomya 

 •apetorum, attacks onions, and the third, 

 I'ogomya fusciceps, attacks chiefly the 

 roots of corn and beans. This last species 

 is seldom very troublesome, so we shall 

 not discuss it. 



The adults of the root-maggots are flies 

 ry like house flies. The life history s 

 ifiefly as follows : The flies emerge from 

 the .soil in spring, lay their little, white, 

 elongated eggs on the ground around the 

 base of the plants, or sometimes on the 

 stem itself. In four or five days the eggs 

 hatch and the tiny white maggots at once 

 attack the neighboring roots. When full 

 grown the maggots cease to feed and 

 change to a brownish pupal condition in 

 the soil close to where they feed. After a 

 few days adult two-winged flies emerge 

 from these cases, and lay eggs for a sec- 

 ond brood. These adult flies resemble 

 the house-fly but are smaller and more 

 slender. In some cases there seems to be 



I third brood. The winter is spent by 

 e cabbage root-maggot in the pupal 



^l5ri( 



maggot in the adult stage. The species 

 that attacks the cabbage and closely al- 

 lied plants seldom does much damage 

 after the end of June, whereas the onion 

 root maggot continues to be destructive 

 all the .season. 



A mean.-; of control is the destruc- 

 tion of weeds like mustard, cress and 

 shepherd's purse, which belong to the 

 same family as the cabbage and radish, 

 and some of which are host plants for the 

 insects. 



Another means is the u.se of carbolic 

 emulsion or of white hellebore. The car- 

 bolic emulsion is made as follows. Boil 

 one quart of soft soap or one pound hard 

 soap in one gallon of water. When i.oil- 

 ing add one-half pint of crude carbolic 

 acid. Boil for a few minutes longer and 

 stir thoroughly until well emulsified. The 

 emulsion can then be stored away and will 

 keep for several days. When using, it 

 should be diluted by adding fifty gallons 

 of water to each gallon of the emulsion, 

 and sprayed directly upon the growing 

 plants and around the roots once every 

 week from the time they appear above 

 the ground or the cabbages are set out 

 until about the end of June. Onions may 

 require later treatment. 



The hellebore concoction is made and 

 applied as follows : Steep two ounces pf 

 good fresh white hellebore in one quart 

 of water for one hour, then dilute with 

 water to make one gallon of the decoction. 

 Apply with a watering can with the rose 

 or knob removed a few days after the 

 plants are set out ; five days later apply 

 again, and again in five days after this, 



and a couple of times afterwards at an in- 

 terval of a week until the plants have got 

 thoroughly established. About one tea- 

 cupful should be poured around the base 

 of each cabbage plant. In clay soil es- 

 pecially, it may be necessary to remove t 

 little earth first from around the stem 

 to prevent the liquid running ofl". 



Each of these remedies has given good 

 results but only when thoroughly done. 

 Great care must be taken to do them early 

 enough to prevent the maggots from get- 

 ting a good start, for if this once happens 

 no known remedy can be relied upon to 

 destroy them. The hellebore decoction 

 is gaining in popularity of late years com- 

 pared with the other, and I have met sev- 

 eral men who have had good results from 

 it. Either of these remedies can be used 

 for onions as well as for cabbages or 

 radishes. 



Tomatoes for the Factory 



The Indiana Experiment Station at 

 Purdue has issued a bulletin, No. 144, 

 on growing tomatoes for the canning 

 factory. It may be summed up in the 

 following five points : 



1. It is necessary that greater care be 

 exercised in the growing of the young 

 plants. Millions of inferior plants are 

 now set. They may be the result of poor 

 seed or unskilful growing. In any case, 

 they cut down the yield and profit from 

 the crop. 



2. Prepare the ground more thorough- 

 ly, and give more time, labor and money 

 to drainage and fertilizing. Thousands 

 of farmers are failing in growing toma- 

 toes because thev do not realize the soil 

 and cultural requirements of the plant. 



•^. Cultivate constantly and thorough- 

 ly. It is probable that neglect of culti- 

 vation is responsible for a greater pro- 

 portion of unprofitable tomato yields 

 than any other single factor entering 

 into the production of the crop. 



4. Handle vines carefully during the 

 picking season. In many tomato fields 

 it was observed that careless picking and 

 rough treatment of the plants so cut 

 down the total saleable product that the 

 cash returns barely paid for the expense 

 of growing and marketing. 



5. Plant smaller areas and practice 

 more intensive methods of culture. 



Within certain limits, vegetable grow- 

 ing pays in proportion to the amount of 

 manure added to the soil. — George Syme, 

 Jr., Carleton West, Ont. 



The green cabbage worm makes in- 

 roads on the cabbage and cauliflower 

 plants, but it is easily kept in check, eith- 

 er by hellebore or paris green. The best 

 plan is to mix these ingredients with land 

 plaster or lime and dust a little in the 

 ' heart of each plant. The hellebore is 

 most satisfactory. 



