Forest Management Diseases and Pests that effect a good harvest stand

What is a Disease? §Definition l disorder that is caused by something specific with consistant symptoms. §Types of Diseases… §Abiotic l nonliving agent cause §Biotic l living agent causes fungus, bacteria, parasite, virus, nematodes

Fungus §Most destructive in forests §Threadlike plants that do not make their own food. §Parasitic- when taking food from a living tree §Saprophytic- when taking food from dead trees to aid in humus production.

Biotic Diseases of Trees

Wood Rots §Cause: l Fungus decay in trees l Break down cellulose and lignin in cell walls l Very harmful because they are hard to detect from the outside of a living tree. §2 Types §White Rot- break down of cellulose and lignin in the cell walls. §Brown Rot- only break down cellulose §70% of all timber lost

Biotic Disease continued... §Symptoms l Conk- specialized growth on outside containing fungal spores spread when opened. Look like mushrooms growing on the sides of the trunk §Prevention l Prevent scaring of trees l Rotate harvest age l Harvest more frequently in mixed age forests l Using these methods doesn’t give fungus the chance to grow.

Canker §Cause l fungus entering through wounds in the bark l cause lesions that produce callus tissue and damage the woody tissue of the tree, making it less valuable §Symptoms l weak trees l decay for no apparent reason l lesions may be present

Canker §Treatment l Eliminate infected trees from the stand §Prevention l avoid scaring trees l discard infected trees

Rust §White Pine Blister l fungus disease that contain different spores; effects trees, currents, and gooseberries. l White Pine and Oak is very susceptible §Fusiform l fungal disease that affects Southern Pine and some Oak.

Rust continued... §Symptoms l spotted red or brown discoloration of stems and/or leaves l may infest in cones, needles, and stems of conifers l infest only leaves of certain hardwoods §Treatment/Prevention l fungicidal treatments l plant resistant varieties l rid host plants l ** All fungi that causes rust spends its live on two different unrelated host plants

Wilt §Cause l fungus invades and grows in the vessles of the xylem tissue. l Why is this harmful? l EX) Dutch Elm Disease is a form of wilt. §Treatment/Prevention l Eliminate insects as they spread disease l discard infected trees l be award of root graft tree roots grow together underground

** Notice that the oak trees affected by wilt will drop their leaves in the middle of summer. All three trees in picture show signs of wilt

Sunscald §Cause l direct sunlight for extended amount of time l freezing temps followed by a few days of hot sun in late winter/early spring §Symptoms l bark damage l color change §Prevention/Treatment l None l weather related

Insects §Types of Damage l Bark Borers l Defoliators l Root Feeders l Terminal Feeders l Sucking Insects

Bark Borers §Bore tunnels into bark and woody parts §Female lays eggs in tunnels §Larvae feed on xylem and phloem tissues §Why is this a big deal?

Defoliators §Insects feed off leaves and needles §Few insects can completely remove foliage from tree in a single season §How does this affect the tree? §Birch, Maple (both black and sugar)

Root Feeders §Destroy the rooting tissue when tender and prevent growth. §Insects include: wireworms, grubs, weevil §Why is this a concern?

Terminal Feeders §Insects that feed on terminal leaders l terminal leaders determine which way a branch will grow §Cause deformities in branches and quality of trunk is reduced. §Insects include: Pine moth and weevil

Sucking Insects §Insects equipped with mouthparts that imbed into the leaves and suck out all the chlorophyll and produce honeydew. §Why is this bad?? §Insects include: Aphids, mites, leafhoppers, lice, scales, cicadas, spittlebugs §Affects all trees

Air Pollution §Abiotic disease caused by Sulfur and Nitrogen compounds given off by exhaust fumes and factories §Damage occurs in leaves and effects photosynthesis

How can we control these problems? §Mechanical/Biological Control l remove dead, decayed trees l invite birds into territory l introduced predator insects ex)ladybug, ants §Chemical Control l insecticides, fungicides l must be careful when applying

Integrated Pest Management §IPM makes use of all methods in a safe way §depends on the use of natural insects first then adds other defense mechanisms §Encourages genetically engineered resistant crops to be planted