Category: Ailments

LEAVES: On Cattleyas, Have Purplish Spots

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Many pigments are masked until a cultural change takes place; higher light levels turn leaves purple; also, a nutrient deficiency can cause the color to appear; the areas around insect punctures tu... Read More

LEAF-SPOT: Phyllosticta pyriformis

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago It is infrequent in Florida; it blemishes the leaves; starts as tiny slightly yellow spots, sunken, which enlarge and turn tan to dark brown or red with black margins; control with benomyl (Benlate... Read More

LEAF-SPOT: Septoria selenophomoides

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Usually found on imported plants; starts as tiny yellow lesions, enlarges and turns dark, the spots coalesce; leaves soon fall and promote more infective spores; spray with benomyl (Benlate 50W) at... Read More

LEAF TIP BURN: Diplodia laeliocattleyae

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Sometimes found on cattleyas in Florida; small, yellow areas on top or bottom of leaf turn brown and become black, greasy areas; fruiting structures develop on older leaves; destroy all leaves; tre... Read More

LEAF TIP BURN: Phyllostictina pyrjformis

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Leaf-spotting fungus infrequent in Florida and not destructive but makes plants unsightly; tiny, slightly yellow spot, sunken, becomes larger, tan to dark brown; red to purple-black margin; round s... Read More

LEAVES: Sunburn Treatment

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Saturate a large amount of water in a pail with sugar and cover the plant in it to seal the tissues from fungi and bacteria and stop dehydration; after an hour or two remove and keep the burned are... Read More

LEAVES: Testing for Virus

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago The expert relies solely on visible symptoms on leaves where they are apparent; the lower portion of a maturing leaf in doubtful cases can be sent for instance to Florida West Coast Scientific Labs... Read More

LEAVES: Wrinkled, Especially the Front Ones

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago This indicates something seriously wrong with the plant; the beginning grower should check the roots and all cultural procedures. A72-117 Read More

LEAVES: Wrinkling on Cattleyas

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago This is caused either by overwatering or under-watering, so take your pick; disease is not likely to cause it; also, check the roots. A81-969 Read More

MALATHION: Toxicity Reactions in Humans

Author is Robert M. [Bert] Hamilton (Compiler), posted almost 8 years ago Nausea, vomiting, diarrhea, salivation, nasal discharge, congestion, nervousness, tremor, dizziness and convulsions. A68-583 Read More

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