Tree Decay Fungi. Chelsi Abbott, MSc The Davey Tree Expert Company

Transcription

1 Tree Decay Fungi Chelsi Abbott, MSc The Davey Tree Expert Company

2 Overview Dangers in Tree Care Industry What are fungi? Why wood decay fungi are important Different groups Specific types of decay & wood decay fungi

3 Why the Concern? 153 tree care related incidents in 2016 (TCIA) Tree Failure can Harm: People Utility Lines Buildings Vehicles

4 Fungi Eukaryotic Non-photosynthetic Decompose and absorb organic matter Mushrooms, mold, mildews, rusts etc.

5 Fungi Beneficial fungi Damaging fungi Crucial to the life cycle of the forest

6 Three components of Disease 1. Host 3. Environmental conditions 2. Pathogen

7 Disease Triangle Pathogen Disease Host Environment

8 Wood Decay Fungi Two main groups: Basidiomycetes: Most common group of fungi for wood decay. They have mushrooms/conks as fruiting bodies Ascomycetes: Second most common group of fungi, with only a few wood rotter's. Small, irregular fruiting bodies

9 Signs vs. Symptoms A sign is physical evidence of a causal agent Mushroom Spores A symptom is the plants reaction/expression to the infection Chlorosis Leaf spot Death of tissue

10 Tree Decay Fungi: Mushroom and conks are obvious sign Some trees do not show above ground symptoms Significantly affect the health and structural integrity of the tree Create hazardous trees- our goal is to protect people and property

11 Just because you don t see doesn t mean it s not there!

12 Things to look for: Fungal fruiting bodies: Conks, mushrooms, etc. Canopy decline - if canopy is declining it could be a problem from below Remember! A full canopy does not mean structurally sound!

13 Symptoms associated with wood rots Crown dieback Leaf chlorosis and necrosis Wood rot Bark peeling away Discolouration of bark Eventual death

14 3 Types of Wood Decay White rot Most common decay fungi - hardwoods Leave behind white residue Brown rot More frequently found on conifers Leave behind brown residue Soft rot Not visibly different than brown or white rot in living trees

15 Types of Wood Decay White rot: Leaves a white or bleached appearance to wood Wood feels moist, soft and spongy Degrade lignin (constituent of cell walls) & erode cellulose Significant strength loss only in more advanced stages of decay Example: Armillaria spp.

16 Types of Wood Decay Brown Rot: More frequently found in conifers than hardwoods Brown, brittle lignin Decays cellulose and hemicellulose Significant amount of strength loss in initial stages of decay Example: Chicken of the Woods

17 Types of Wood Decay Soft Rot: Attacks cellulose Attacks links between cell walls and lignin Loss in wood structural quality Example: Kretzschmaria deusta

18 How Do Wood Rots Gain Entry? Stressed trees Construction damage Soil compaction Mechanical damage Insect/animal damage

19 Important Wood Decay Fungi Armillaria Spp. Ganoderma Spp.- Artist s conk & Varnish conk Laetiporus sulphureus - Chicken of the woods Inonotus dryadeus Xylaria polymorpha - Dead Man s Fingers Kretzschmaria deusta

20 Armillaria Root Rot Hosts: Many deciduous trees and conifers Also called: Shoe-string rot and Honey mushrooms Multiple species Infects stressed trees through wounds Can infect roots via rhizomorphs Aggressive

21 3 Signs of Armillaria

22 Not to be confused with Velvet shank Jack o lantern

23 Ganoderma applanatum Hosts: Most hardwoods, Maples, Oaks, etc. Also known as Artist s conk Perennial conk Infect via wounds Decay can extend 1-2ft above and below conk White rot Aggressive

24 Ganoderma applanatum

25 Ganoderma applanatum- Artist s Conk G. Jones

26 Ganoderma lucidum Hosts: Most hardwoods, honey locust, Maples, oaks Also known as Varnish Conk Annual conk Kills cambial tissue of roots White rot Moderately aggressive

27 Ganoderma lucidum

28 Chicken of the Woods (Laetiporus sulphureus) Hosts: Most hardwoods, oaks, black cherry, etc. Choice edible Fruiting body emerges from summer to fall Brown rot Causes extensive decay

29 Chicken of the woods

30 Hen of the woods Hosts: Hardwoods, predominately oaks Choice edible Fruiting body emerges from September to October White rot Weak pathogen Theforagerpress.com

31 Inonotus dryadeus Hosts: Hardwoods, Oaks, etc. Also known as weeping conk Annual but persistent Slow progressing white rot Excessive decay could mean trees are at risk for windthrow Found at crown (close to ground) or on roots

32 Inonotus dryadeus

33 Dead Man s Fingers (Xylaria polymorpha) Hosts: Hardwoods including Maples and beech Black finger-like structures (stomata) appear in spring White rot of base and roots Can kill cambium Only attack stressed trees

34 Dead Man s Fingers

35 General Wood Rot Management No management available once infected Destroy fungal fruiting bodies Avoid wounding the tree General plant health care

36 Things to take home Always ask if you re not sure Presence of a conk is (usually) a bad sign Just because there isn t a fruiting body, doesn t mean there isn t decay