Page 22 - Griffin Gazette Q4 2017

By Rick Yates, fatal. Equally problematic, adult fungus larvae are not directly damaging to plants.
GGSPro Technical gnats and shoreflies are known to spread Habitat Management
Services Manager root and crown rot diseases in their travels. Habitat modification and sanitation is the
Fungus gnats and Proper identification of fungus gnats and first line of defense against fungus gnats
shoreflies are a shoreflies is important for control; some and shoreflies. Fungus gnats lay their eggs
nuisance, there's differences in chemical and biological control in cracks and crevices in the soil media. In
no debating that. options need to be accounted for. Adult greenhouses this most often occurs on the
They make insect- fungus gnats are dark, delicate-looking flies, surface of the soil but can occur in drain
leery customers similar in appearance to mosquitoes, with holes in the sides and bottom of pots as
uncomfortable and slender legs and long segmented antennae. well. Constantly moist soil media, and the
they leave their Their wings are clear with a distinctive “Y” algae it encourages, make a suitable habitat
calling cards (fecal matter) on the foliage shaped vein. Fungus gnat larvae have a for fungus gnat larvae. Shoreflies live in
of otherwise beautiful plant material. More shiny black head and an elongated, whitish- consistently damp areas with abundant
than one grower has inhaled these tiny to-clear, legless body. Shorefly adults more algae. The larval stage feeds on algae and
flies while hard at work in the greenhouse. closely resemble miniature house flies. the pupal stage is semi-aquatic, partially
Yuck…. That's not where the list of offenses Compared to fungus gnats, shoreflies are submerged in water.
ends. Fungus gnats are a major pest of stronger fliers and have shorter legs and Moisture management, including improved
greenhouse crops, but don’t often get antennae. Shoreflies have five distinctive drainage and taking steps to limit algae,
the attention they deserve. Direct plant clear to white spots on their wings. Shorefly can pay dividends in terms of creating a
damage occurs through larvae feeding larvae are also clear to white, but lack a less favorable habitat for pest development.
on roots, in stems, and occasionally on distinct head capsule. The pupal stage is Power washing and use of approved
foliage, especially leaves in contact with the dark brown and has an interesting “fork” cleaners, such as Strip-it Pro, can be used
growing media. For seedlings and cuttings structure on one end. While shorefly adults to remove organic matter from surfaces
in propagation, the damage is sometimes are able to spread plant pathogens, the
between crops. After a thorough cleaning,

Table 1:
Product Active MOA Fungus Shoreflies Comments
Name(s) Ingredient Gnats
Adept Diflubenzuron 15 X X IGR, sprench, 21 days of control
Citation Cyromazine 17 X X IGR, sprench, vegetable transplants

Distance Pyriproxyfen 7C X X IGR, sprench, soil surface spray, 21 days,
Fulcrum Distance- fruiting vegetables
Gnatrol WDG BT- israelensis 11A X Make 3 applications 1 wk apart
Pylon Chlorfenapyr 13 X Soil surface spray only, 7-14 days
Safari Dinotefuran 4A X X Soil drench, vegetable transplants

22 | Griffin Gazette 2017