| Good sanitation procedures are still the first line of defense against these
potentially destructive pests. Products such as Greenshield, Triathalon, and Zero-Tol can
be used according to label directions to control algae that serves as a breeding area for
fungus gnats and shoreflies. Fungus gnat larvae can destroy root tissue, and tunnel up
into stem tissue causing death of the plant. The adult stage has been shown to move root
rot disease organisms from pot to pot in their travels. |
| Most control efforts are targeted at the larval stage. The list below is not intended to be exhaustive; products other than those listed may be safe and effective. |
****Read and follow all label directions****
|
| Adept - one 1 oz water-soluble packet per gallon of water through a 1:100 injector used as
a soil drench. Apply only enough to wet up the top inch or two of soil. The label contains
specific ounces per pot recommendations that must be followed to insure safe and
effective use. Treat crops and floors where fungus gnats may breed. Adept is an insect
growth regulator that stops the larval stage from developing into reproductive adults. Do
not use on poinsettias, hibiscus, or Reiger begonias. 30+ days of control. 12 hr REI |
| Citation - Use one 2.66 oz packet per 100 gallons as a drench or soil surface spray to all
surfaces where fungus gnats may breed, including growing media, under benches, etc.
Insect growth regulator. Repeat on a 7 -14 day schedule to minimize re-infestation.
Syngenta also recommends fog applications of 2.66 oz per 1/2 acre (22,000 sq. ft). Do
not apply through any type of irrigation equipment. 12 hour REI |
| Distance EC - Soil surface spray to control the larval stages of fungus gnats and
shoreflies. 1/3 to 1/2 teaspoons per gallon, 6-8 oz per 100 gallons. A drench can be used
instead at 2 oz per 100 gallons applied only heavy enough to saturate the top 1 to ½' of
soil. Don't drench plants under water stress. Do not use on salvia, Boston fern, schefflera,
heuchera, or poinsettia bracts. 12 hr REI |
| DuraGuard - Apply 1/2 oz per gallon as a coarse soil surface spray to all areas where the
larvae may breed. Treat soil when it is already moist and apply enough spray material to
thoroughly wet the soil surface. It can also be applied as a soil drench at 25 oz per 100
gallons. Repeat at 7 -14 day intervals. 12 hour REI. Note: DuraGuard is now a restricted
use pesticide in all states with a 24 hr REI. |
| Gnatrol - Apply 2-8 pints per 100 gallons as a soil surface spray or drench to thoroughly
wet the surface of the soil. Experience shows that the high rate must be repeated three
times at seven day intervals to control severe populations. Natural product (BT) with a
four hour REI. |
| Nemasys or Nemashield - Beneficial nematode (Steinernema feltiae), shipped live from
the rearer to the grower at time of use. Applied as a coarse spray. Immediately rinse
nematodes off of leaves and in to soil after application. Re-apply at 14-21 day intervals.
No re-entry interval is required. |
| Pylon EC - 1/6 to 1/3 teaspoons per gallon applied as a soil surface spray. Maximum of
two applications before rotating to another chemistry. No visible residue but may burn
some open blooms. Read phytotoxicity cautions on the label. 12 hr REI |
| Safari SG -
4-6 week systemic control of larval stage. Drench 1 tsp to 1.5 tsp per gallon or 8 to 12 oz
per 100 gallons (apply 4 oz per 6" pot). Do not rotate with Flagship, Marathon or Tristar. Excellent plant and bloom safety. 12 hr REI. Not labeled in NY as of 3/05. |
| Controlling the adult stage has been difficult in recent years, as most of the labeled
products have not provided adequate control. Conserve SC has been reported by many growers to provide relief from the adult stages of fungus gnats and shoreflies. This use is
not on the label, but it is legal to use a product on an unregistered pest as long as the site to which it is applied is registered. |
| Conserve SC - 3/4 teaspoon per gallon, or 12 oz per 100 gallons as a foliar spray controls
adult fungus gnats and shoreflies. (This treatment may be more effective when tank
mixed with Talstar GH at 1 teas per gallon or Decathlon at ¼teas per gallon. Both have
12 hr REI's). No flower damage or visible residue. 4 hr REI |
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