Bryobia mites are brownish, flattened mites with very long front legs.
Bryobia mites (cont from last issue)
They overwinter as red eggs laid in similar locations as those of ERM but, in contrast to ERM, the eggs are spherical instead of onion shaped and do not have spines.
Bryobia mites feed on both surfaces of the leaves but during the brighter parts of the day they move off the leaves and can be found on nearby twigs. This is something important to remember when scouting for mites reveals silvering of the upper leaf surface but no mites can be seen on the leaves.
Bryobia mites do not usually produce webbing on fruit trees.
Eriophyid mites
Eriophyid mites (apple rust mite, pear leaf blister mite, and peach silver mite) are tiny (about the size of a TSM leg) worm-like mites that are useful prey to maintain predator mite populations in readiness for when TSM or ERM become active.
The eriophyid mites rarely cause significant damage unless their populations build up to extreme levels due to poor choice of pesticides resulting in decimation of predator populations.
Growers who have disrupted their predator mite populations by choosing to use pesticides that are toxic to the predators, for control of other pests such as woolly apple aphid or weevils, can re-establish predator populations by purchasing suitable predators from commercial suppliers.
These suppliers will also provide information on the impact of pesticides on the predators, so that growers can adjust their spray programs against other pests while still protecting the predator mites.
Pest monitoring
A survey of growers, in all Victorian production areas, conducted in 1999 demonstrated that more than 92% of growers used pest monitoring to inform their spraying decisions and 57% used consultants for advice on pest management based on their monitoring results.
(cont next issue)
See this article in Tree Fruit March 2019
