DISEASES AND PESTS

Dominion, Volume 29, Issue 150, 20 March 1936, Page 18

DISEASES AND PESTS

Attack Them Now You know how in November fun -old diseases—and insect jiests—seem to appear from nowhere. Almost every kind of plant is laid under toll. Sometimes it is the übhiuitous greenfly which goes for anything bearing a leaf. At others the foe is more discriminating. like leaf mining maggot in chrysanthemums, or streak in sweet-

When you come to think of 1:, though, these troubles cannot appear from nowhere. They aren't created, but arc hatched from eggs and spores that have over-wintered either on vegetation or in the soil. It you can recollect leaving about an unhealthy plant you might have destroyed, you have hclited the enemy you desired to kill. From now onward, as the various beds and borders are cleared or eut down, examine the growth and, if bears the least sign of ill-health, bij-u it. Only if the growth is clean should it be chopped up and incorporated into a compost heap, where it ''’ill quickly decay and help to supplement your stable manure supplies. On no account pile this spent stuff ol the rubbish heap and leave it to decay there It might oil doing sb contract a-,disease or be attacked by an ins’jct pest. In any case it will harbour slugs and other pests. By the way. the compost heap .s built by stacking in rotation 6in. thick layers of good garden soil, littery stable manure and the yegetablc refuse. Clean all the- stakes before puttlug them away. Strands of raffia ami strips of leaf or stem clinging to stakes- are perfect breeding grounds for insect pests ami diseases. Roses call for special notice. They are attacked, by two serious leaf diseases—mildew and black spot. Leal fall is rather a long job. It starts at tile end of March and often continues until early June. Unless you make a weekly job of raking up the fallen foliage, It may blow into inaccessible corners, there to carry its destructive cargo until another, year, when it will infect young leaves. Don’t forget the weeds. They are plants just like the flowers you cultivate. and like them subject to the attack of pests, which they pass on. Have a thorough clean-up; burn the unhealthy weeds, and nils the healthy ones with the compost heap. To destroy soil pests, soil treatment is essential. 4 If. for instance, your asters wilted badly, fork Gin. deep into eneh square yard of affected bed (loz. of freshly-slaked lime, which kills the spores before they fall into their most tenacious resting stage. Where sweet peas have suffered from streak, give an application of kainit (2oz. per square yard). In addition to potash, which definitely restrains this disease. kainit contains chlorine, 'which is poisonous to the streak organism. Lose no time in using the kainit, to

give the poison a chance to wash out before anything is sown or planted in the ground next spring. Where wireworm has been trouo'.esome among border chrysanthemums or an old earnation bed which has just been cleared, spread on the surface of each square yard 2oz. of a mixture of equal parts naphthalene and freshlyslaked lime, and fork it in 4in. deep. Tn a short time the pungent gas generated by this mixture will destroy every wireworm in the bed.