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Tiny green/white/yellow or pink insects; Live and feed in colonies on young growth, buds or flowers. Stunt plant growth. As aphids secret a honey dew, they are "herded" by ants, who harvest the secretions; Believed to be vectors for spread disease.
Treatment:
Malathion- I teaspoon (t) per Liter (L) spray. If plants have buds or flowers use Cygon water as drench or Safer's soap, diluted 1:40. Diazinon I t. per Liter Outox 1-2 t. per Liter
Small white cottony immobile insects. Form colonies at stem joints & near base of leaves (usually on underside) and in young growth & under bracts.
Treatment:
same as aphids.
Commonest destructive pests. Feed nights and cool days. Hide on warm days. Leave silvery slime trail.
Treatment:
Methaldehyde product placed around pots and/or around bulb carrying flower spike.
Small insects attach to stems, leaves, bulbs & rhizomes. Generally covered with protective shell, form colonies. Can spread fast, often moved by ants.
Treatment:
70% isopropyl alcohol. scrub with toothhbrush entire plant, spray once a week for 3 wks, spray once a month thereafter. Cattleya scale is cottony white.Safers soap 1:10 dip
Soft squishy dark brown/black areas on leaves frequently circular. On bulbs, blackened area extending to rhizome.
Treatment:
Cut off infected parts %L seal with Tree Seal. Use Natriphene or Dithane M-45 per box directions. Physan or RD 20 are also good, but have little residual. Ground cinnamon will dry up the watery areas. Run dry.
Dry blackened area extends from tip of leaf downward, usually caused by migration of excess fertilizer salts. Treatment:
Cut off leaf tips with hot sterile tool. If excess salts are noticeable in potting media (caked white mineral buildup), then repot with fresh media. Then water normally several times with clear water. If recently repotted, flush potting media with clear water several times. Also can be the result of cold damage and/or heat stress. If so, adjust enviromental temperature controls.
Worst of summer pests. Fine grey stippling on leaves with fine silvery webs on underside: need hand lens to see them. Most common is the red spotted mite.
Treatment:
Shows up where the cells in the leaf has been killed. White stripes. In flowers shows mottled appearance. Spread by mechanical means.
Treatment:
isolate or destroy infected plant. No cure. Flame all cutting tools to prevent spreading. Sterilize all cutting tools to prevent spread of virus.
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