Forestry Notes FOREST HEALTH NORMAL – Biological processes Resilienent to SHORT term stress Adapt to LONG term changes MOST trees are healthy, some are not Forest is SATISFYING mgmt goals Normal - Photosynthesize and respire - Absorb water and nutrients - Translocate water and sugar - Grow - Reproduce Short - Want a forest to be healthy enough and able to bounce back from stress Drought Flood Frost Defoliation Long - Climat change - Precipitation - Temperature Most - Some trees are dead and diseased, this is a good thing. - Allows for decaying and redistribution of nutrients and energy of the dying trees Satisfying - Water…Fish - Habitat… Biodiversity - Recreation - Timber - Carbon Definition of a Healthy Forest - Conditions where… Biological processes are not significantly impaired - There is… Resilience to short stress events Ability to adapt to long term environmental change A mix of healthy, dying and dead tress - And… Mgmt goals are met DISTURBANCE AGENTS FIRE INSECTS DISEASE MAMMALS ABIOTICS Fire - Intensity, will is burn a small patch? Or the entire forest? Insects - Bark beetles - Defoliators - Terminal weevils Disease - Root rot - Wood decay - Dwarf mistletoe - Stem cankers and rusts Mammals and Abiotic - Squirrels - Frost crack Introduced - Chestnut blight (1900) - White pin blister rust (1910) - Dutch elm disease (1928) - Balsam wooly adelgid (1900) - Gypsy moth (1860) SCALE OF DISTRIBUTION Endemic vs. Epidemic Endemic - Usual level of death - Kills individual trees (good) Fallen tree act as habitats for other species Increased stand biodiversity Less intertree competition Epidemic - “out break” - Often stand replacing Impared functions (photosynthesis, growth) Values (water, recreation) - Increased landscape diversity Can destroy a stand but not others = patchwork MANAGEMENT The triangle Environment Host Pests Short term- target pest - Stumping for root rots - Pruning for stem rusts - Trapping insects - Remove infested trees - Pesticides- mainly defoliators Long term- healthy forest - Stand vigor Stand density (spacing) proper species A vigorous stand is more resilient - Mixed species Many pests “species specific” A mixed-species stand is more resilient - “mimic” natural disturbance size and frequency break-up landscapes mosaic Many pests are “age specific” A diverse landscape is more resilient Study of the relationship - Disturbance agents - Forest (tree) condition - What we want Intersection of several disiplines - Pathology, entomology, fire - Tree- botany (tree physiology) - Stand- ecology (disturbance and succession) - Siviculture - Harvesting FUNGI BASIC STRUCTURE - Hypha - Septum (pleral= septa) with pores - Growth at tips - Mycelium - The mushroom Hypha - Single strand of single cells surrounded by a tubular cell wall Septum - Cross walls between hypha cells. - They have pores to allow movement of materials Mycelium - Mass of hyphae that form the vegetation part of the fungi VIDEO #1 - Heterotrophs consume organic carbon (E) - Mycelium break down nutrients with enzymes and take it in. - Mycorrhizae= Plant + fungi relationship 90% of plants - Toadstool and mushrooms= fruiting bodies Spores= asexual and sexual reproduction - Yeast Budding= asexual reproduction Fermentation - Disease causing Athletes foot Lung infection Trush - Disease stopping Penicillin CHARACTERISTICS - Heterotrophic Secrete enzymes into the world to take in nutrients - Lack of mobility - Cell wall Composed of CHITIN (glucosamine) - Multicellular (except yeast) - Typically haploid (1N) - Spores Asexual and sexual reproduction VIDEO #2 - Filter sediment from water - Largest organism on earth is a honey mushroom 1 cell thick - Endophilic fungi Live inside the tree LIFE REQUIREMENTS - Nutrients (vitamin) - Energy source - Suitable temperature (0-40) - UV protection - pH level (4-6.5) change in pH can cause enzymes to denature - H2O - O2 3 Ways Fungi Get E (Sugar) 1. Symbiont/ Mycorrhizae Sugar from plant Give nutrients to plant 2. Saprophyte (decomposer) Break down and consume dead organisms 3. Parasite ROLE OF FUNGI - Saprophyte= Decomposers - Parasite: energy from living host If the host is not impaired, it is not a disease If it hinders the host, it is a disease ****Disease in the state of impairment and the pathogen is what causes it**** - Symbiont: Symbiotic relationship TAXONOMY O-Z-A-B-D OOmycetes ZYGOmycetes ASCOmycetes BASIDIOmycetes DEUTEROmycetes OOmycetes - Water molds - (lower/ not true fungi) - asexual spore swims - eg PHYTOPHTHORA important because it’s the reason for the potato famine and sudden oak death ZYGOmycetes - Airborne spores - Eg some mycorrhizae ASCOmycetes - Airborne sac “8 in a sac” - Fruiting bodies grow on leaves and tress when conditions are right, the spores go wild - Tare spots Eg foliar, canker, and vascular wilts Block water exchange= bad BASIDOmycetes - Airborne spores - “4 spores on a club” (naked) - spores in gills eg. Decay/root rots and rust DEUTEROmycetes - Air borne, no sex.. yet - Holding bank for fungi that we do not know which group they belong to bc we have not seen them mate sexually Life cycle - Mushrooms spend most of its time as a (1N) Spores grow as 1N There might be another one that lands beside it and if their hypha like eachother they will be friends (n+n) WOOD DECAY Wood structure - A tree is a series of boxes or “compartments” framed by annual growth rings and rays. Growth rings = seasons Spring wood = less dense bc it grows faster Latewood takes longer to make - Ray, at the bottom of the rays there are resin ducts Resin is a defense mechanism Resin ducts also found in the latewood more than springwood - Ring and rays act as walls Cells - Chemical components Leaf= sugar factory Cellulose 40-50% (long glucose chains) Hemicellulose 25-30% (branched sugars) Lignin 25-3-% (amorphous) Extractive 3-5% (phenols, waxes, terpanes) **cellulose= energy store of sugar strength (rods) Lignin - amorphous means blobish - surrounds cellulose - Extractives Most are poisonous - Analogy Rebars= cellulose for strength Concrete= lignin Decay Process - Starch acts as glue Made up of sugar but it’s a slow release - Decay = digestion Energy gets released Envolves enzymes Chemicals - Enzymes Cellulose (endo and exo) Lignase - Chemicals H2O2, Fe+ - Exocellulase cuts off the sugar (2 sugars) from the chain of 10,00 Endocellulase breaks the large sugar chain in the middle and allows for more active exocellulase sites. Before we can get to the cellulose, we must break down the lignin by using lignase Decay Rate - Enzyme half-life Fungus want to control the rate of decay by controlling the rate at which they release enzymes - Sugar and enzyme production When there is lots of available sugar, the rate at which enzymes are released stops/slows Decay… - Western red cedar Have lots of chemicals Sucession of different microorganism break down the poisons and allow for decay fungus to attack the tree But… when the tree gets cut down, the poisons are still there that havnt been destroyed and that’s why its good for going on houses *Animation* - Starts with phenolics and thujaplieins (poisons) - Phase one of sucession= agent ‘S’ ‘sporotrex’? Kills phenolics - Colour of moist poisons Straw color, purple, brown, white (most to least poisonous) - Special agent ‘K’ comes in and kills thujapliens - Then rot goes in and kills the tree Decay by Digestion - White rot- the tree gets digested in the localized area - Brown rots- No pits, but craking into vubes because its shtinking and dry White rots Lignase, cellulose (exo and endo) are used to break down the wood for digestion 1st selective delignification (biopulping) gets rid of lignin (the brown) - Then exposed cellulose then decayed - … decays all wood components - White bc “bleaching” and lignin gone localized (pits, stringy or layered) surrounding wood intact (pulp nd wood strength) Layers bc the spring wood is easier to digest - White rot is stronger than brown rot at early stages - Brown rot - Only has exocellulase - H2O2 and Fe+ (small chemicals), exo-cellulase - Small chemicals penetrates lignin and breaks cellulose in the middle because enzymes can’t get in - Enzymes enter and decay cellulose ** when white rot is complete and it completely digests the wood When brown rot is complere, it only leaves the lignin behind …. But in the earlier stages, white rot is much stronger TREE DEFENSES Constituent (=built-in) - Lignin protects cellulose - “compartments” (latewood and rays) Toxins- heartwood Cork- waxes ( hard to get through) Resins - When sapwood converts to heart wood, it creates toxins and changes colour as it dies - Trees that grow faster usually have less defense mechanisms Induces (= in reaction to) - Resin flow to injury - Callous over - Periderm- cork If the fungus gets past the first cork layer, there will be another layer of cork grows behind it. Codit (compartmentalize of decay in tree) - Reaction zone (exsisting wood) (sapwood) - Wall 1- vertical Fungud can travel through the xylem Weakest Plugs vertical vascular system - Wall 2 – inward 2nd weakest existing latewood may be enhanced with toxins waxes resins (TWR) latewood fungus has a hard time getting in because it has to pass a ton of latewood layers - wall 3- sideways strongest of 3 walls existing rays also may be enhanced with TWR - Barrier zone (new wood) Wall 4 – outwards Strongest wall New “ring by cambium” Protects new wood o Trees make a layer of super incredibly full of TWR and be in penetrable some trees are better at this ie. Hardwood takes a ton of energy so only does it once tree rots from the inside Indirect - antagonism (endophytic fungi) - wet wood Has a column of water in the middle with no oxygen to reduce growth - Endophytic fungi will will fight against other fungi trying to come inside The fight produces a separation between the two fungi and creates a barrier of black lines “spalting” Decay location - Saprots-> sapwood When it dies its super suseptable to decay No defenses (saprophyte) - Heartrot-> hearwood True heart rot Wound invader True heart rots - Coming into like standing tree (3 spp) - No wound (trojen horse) Heart woodrot gets into the tree by a broken branch. If colonizes and goes dorment and waits until the tree regrows ovr it and it ends up inside where it can go ham. - Hrtwd only - Conks on live trees - Obligate (die when tree dies) - The tree is okay and the living tissue is not attacked very much - Cannot go to the separation to sapwood bc defenses are too strong - Conks are for sure heartrot Often on branches **** examples: Echinodontium tinctorium. Phellinus pini, P. tremulae (P. Ignarius) Wound invaders - Needs wound (primary vs secondary) - Mainly hrtwd (sometimes sapwd) - Conk seldom on live tree Facultative ~ 38 spp in bc *** Live trees rot inside out and dead trees rot outside in*** MANAGEMENT Tree age - Hemlock in the interior is shit but on the coast its awesome - Coast of interior can cause a difference in tree growth Adcanced regeneration - Tiny trees that are 100s years old - Not great bc it will often have decay, wounds and fungi Rotation age - When you cut it - Older trees will decay faster than they grow Net Volume - Decay waste breakage (DWB) factors (studies have been done so now when we see scars we can estimate the amount of decay) - Call grade net factor (CGNF) Person will go and make an assessment based on experience (BETTER) Dead standing - Small tree vs big tree Big tree last longer - Species matters - Wet sites decay faster - Bark beetle kill and shelf life? How long is the dead tree going to be viable for - When the trees are dead, you want to take them when they are still healthy. 4yrs-16yrs Other values - Wild life habitats Bear den - Recreation -> safety tree assesors - Carbon -> dead trees release carbon - There are people that can asses wildlife vs danger of a tree Unacceptable Damage - Free growing (FG) trees Wound > 33% circumference > 20% length scars okay **** as soon as you start cutting trees, you need free growing trees to be growing. Young, above brush, free from disease. Retention Period - How much time before I come back to get the tree - Short vs long vs uneven-aged Spp affects this Uneven age means that there is no clear cutting and only take older trees Has more likely going to be bad, because when you’re removing big trees, could hurt younger ones Tree Species - Simple version Broad leaf The rest F and P Damage (big tree) - Wound size – 400cm2 = threshold (size of hand) - % circumference 50% - F and P 33% - the rest - wound – bark ripped off and no wood is hurt - gouge (bad)- sapwood is hurt unacceptable always ROOT DISEASE Tissues - Even small roots the size of thumb have woody tissue Bark toxins Before it dies, it builds up toxins Heart wood Resin Callousing over Periderm= cork Fungus gets in and you just grow a wall behind it Root Facts - Typically, 3x’s width of crown, ¼ biomass - Positive geostrophic Grows down (with gravity) - Advantageous Can grow where ever they want to get more nutrients from somewhere - Roots anchor (large roots) - Uptake (fine roots) - Storage of carb’s - Reproduction (vegetative) Clones growing from root - If you see a blown over tree with no root mat = root disease - Connected networth Connections are also being made with mycorrhizae Root grafting - Mycorrihzea Mutualistic ass’n between fungi and roots Waterand nutrients exchange sugar SOIL - Top layer= organic layer L Litter= just fallen matter F fermentation H Humic Mor (acidic in conifers), morder (in between, mild forest), mull ( thin, nutrient richer. Broad leaf site) Ph, fauna, fungi More humos form with conifer More fungi in acidic ph, so lots of mor Mull, you don’t have as much fungi but you have earthworms
