Insect/Disease Flashcards
(28 cards)
Forest Tent Caterpillar
NATIVE
Egg masses in upper canopy
spring/early summer defoliator
Gregarious for the first three instars
Fruit trees and broad-leaf trees
Spongy Moth
EXOTIC - Europe
Silk production
Overwinters egg masses
Pupate into adult under leaves and bark
Mostly hardwoods but may consume and kill conifers
Pheromones’ are used to disrupt their mating
Pine Engraver Beetle
Turning fork galleries
Infests upper part of the tree
Red boring dust can gather around base of tree
Pheromones and funnel traps used for control
Mountain Pine Beetle
Infests middle of the tree
From Montana to the West Coast into Mexico
Turns them orange like fall
Red Turpentine Beetle
Infests lower part of tree
1-2 year life cycle
Obvious signs - pitch tubes on stumps
Emerald Ash Borer
EXOTIC - China
Feeds on phloem of ash
Natural Spread and through firewood
Chemical control but not practical for forest settings
Biological control by releasing wasps are still being analyzed
Red Oak Borer
NATIVE
Hosts are most commonly red oak, black oak and scarlet oak
They extrude frass, discolored bark, wet spots and exit holes.
2 year life cycles
Woodpeckers are natural control and ants
Asian Long-Horned Beetle
EXOTIC - Asia
Treat hosts with insecticide spray or remove hosts .5 miles
Dime sized exit holes
Hosts- Maple and Boxelder
Two-Lined Chestnut Borer
NATIVE
Attacks weakened oak species across Minnesota, broken branches etc.
Feeds and lives in the inner bark and cambium layer of the wood.
Infested oaks die after 2-3 years
Eastern Larch Beetle
NATIVE
Hosts tamarack and planted larch
Control - Sanitation
Larvae are damaging
Galleries under park and wood pecker damage
Yellow of lower crown
Spruce Budworm
NATIVE
Hosts - spruce and fir
Control is commercial thinning, pesticides are not successful for forest management
30-40 year outbreak cycle
Sugar Maple Borer
NATIVE
Host - sugar maple
Horizontal wounds
Larvae take two years to develop
Wounds create pathways for rot fungus
Remove infested trees and having a 10-15 year thinning cycle
White Pine Weevil
NATIVE
Feeds on leaders of young white pine
Control and management including planting with a tighter crown closure
Pruning leaders and damaged branches can save the tree.
Leaf Miners
Insects that feed within the leaves between the upper and lower layers of tissue.
Shelter Feeding
Larvae use the leaves as shelter as they feed on the same leaves
Disease Triangle
Virulence of pathogen
Favorable environment
Host susceptibility
Pathogen
An organism that causes disease
Armillaria Root Rot
Lives as a saprophyte in the soil until it finds a weakened host and turns parasitic
Leaves fruiting bodies near stump
Shoestring rot
Infests deciduous and evergreen trees
Annosus Root Disease
Caused by native fungus
Main hosts are all conifers
Spreads by aerial spores that infect recently cut stumps
Flaky white under bark
Control - trenching and breaking up root graphs or cutting stumps with borax
Hypoxylon Canker
Native
Host - aspen
Causes cankers and weakened portions on aspen, usually breaking off at 15ft up
White Trunk Rot
Native
Host - aspen
Main sign is fruiting bodies on trunk, happens in over mature aspen so rotation is shortened to prevent loss from rot
Butternut Canker
EXOTIC fungus - Asia?
Infects black walnut
No resistance yet
Considered endangered in Canada.
Thousand Cankers Disease
NATIVE
Host - black walnut
Vectored by walnut twig beetle
Dutch Elm Disease
EXOTIC
Vectored by elm bark beetles
Spreads in root graphs
Symptoms result from clogging vascular system of the tree and causes dieback within the crown
Control- Trenching and fungicide injections
