. Florists' review [microform]. Floriculture. OST serious of the pests with which the sweet pea has to contend is the green fly. We find it is respons- ible for what is commonly known as "streak dis- ease," an irregular strip- ing or mottling of leaf and flower. It is only while the plants are small that the Hy is able to infect them. From the time the plants are up until well into September they should be sprayed twice a week with a strong solution of nico- tine. We use a half-pint of nicotine to six gallons of water, put on under strong pressure. If the plants are not exces- sively
. Florists' review [microform]. Floriculture. OST serious of the pests with which the sweet pea has to contend is the green fly. We find it is respons- ible for what is commonly known as "streak dis- ease," an irregular strip- ing or mottling of leaf and flower. It is only while the plants are small that the Hy is able to infect them. From the time the plants are up until well into September they should be sprayed twice a week with a strong solution of nico- tine. We use a half-pint of nicotine to six gallons of water, put on under strong pressure. If the plants are not exces- sively dry, this proportion will not harm them. As the weather becomes cooler, once a week will do, and throughout the winter months we paint undiluted nico- tine on steam pipes every month or six ?neeks. All openings near the ground, such as doors, should be kept carefully closed to guard against the entrance of green fly from outdoors. According to our observation, plants exposed to such openings are seldom free from the streak disease. The pests seem to keep too close to the ground to find their way through a side ventilator. Every Plant Infected. Several seasons ago we planted a newly built house with early peas and postponed the glazing until late Sep- tember, hoping in this way to take ad- vantage of more natural conditions for starting the plants. By November we ilecided that not a plant in the house had escaped the streak disease. Scien- tific investigators diagnosed the trouble as a form of root-rot with which the plants could be infected through aphis. They stated that the germ of this trou- ble was lodged in the soil and advised thorough sterilization with steam or for- maldehyde. We used both disinfectants, leaving out one bed as a check on the others. The next crop of plants in all these beds came equally well. While this does not definitely prove anything, we have had no streak trouble since then, realizing that green fly must be kept down at any cost. Plants affected w
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Keywords: ., bookcentury1900, bookdecad, booksubjectfloriculture, bookyear1912
