The Right Way To Prune A Tree
If you struggle with varmints and critters in your garden, here’s the hard truth … it’s your fault. Your garden represents an abundant concentration of nutrients and carbohydrates that simply do not occur in that quantity anywhere in the natural world. It represents a veritable free buffet to all manner of critters from insects to rodents to coyotes.
Weeds are “plants in the wrong place” and plants who know how to grow better than the ones we want to grow.
What does it mean to have a green thumb? I think most of us understand the term. Green thumb refers to some level of mastery with plants. Plants are, in fact, so complex to master that often I think people with green thumbs possess some level of magical power over them. According to James Underwood Crockett, green thumb comes from the fact that the algae which grows on the outside of earthenware pots will stain a person's thumb (and fingers) if he or she handles enough of them. Hence, a person who is always working with flowerpots literally has a green thumb.
A green thumb also symbolizes the very nature of gardening… that it is always growing, always changing, and always in need of time and attention. It is the nature of the art of gardening to be unlike any other art form in that if you walk away from it for a time, nature will reclaim and her materials and erase your part in the art. Therefore, to see your garden is to know there are humans nearby.
Perhaps another way to understand green thumb is the thumb itself. It is the fact that we possess opposable thumbs which enables us to interact with, alter, manipulate, and care for the world around us with such dexterity. Gardens only exist as the result of human intention.
It’s Fall … Time to Prune
I think one of the most interesting facts about tree care is that if we do our part we can really truly be of help to a tree. Trees don’t always make the best long term decisions for themselves. So the good news is - proper pruning can actually extend its life and health. The bad news is - improper pruning can really hurt a tree.
•Pruning will change the form and growth rate of a plant.
•Pruning can minimize and help prevent insect and disease damage.
•Problems may be prevented by pruning correctly during the formative years.
•Encourages flowering and fruit development.
•Pruning should start at planting
Where does the soul of a tree dwell?
Somewhere in the center of the root ball just below the ground. Don’t anthropomorphize a tree.
How to Prune Large Branches - Master the Three Cuts
1.The Undercut - A few inches away from the trunk on the underside of the branch and about ¼ of the diameter deep. In case the branch splits and tears, this stops the tear from stripping bark down the trunk.
2.The Main - Starts directly above the undercut and comes all the way through. This removes the branch.
3.The Trim - Now that the weight of the branch is gone you can safely trim the remaining stub.
•A flush cut is too large (oval)
•Cut nearly flush to the bark on top of branch and angle away gently to keep cut as small and circular as possible - you want a bump, not a stump
How to Prune Small Branches
•To shorten a branch or twig, cut it back to a side branch
•Or make the cut about 1/4 inch above a bud.
•Always prune above a bud facing the outside of a plant to force the new branch to grow in that direction.
Trees don’t heal, they seal - bark forms a “callus” doghhnut
I was at the Mariposa Grove of giant Sequoias - You can see The Tunnel Tree bark curling into the opening in an attempt to seal the wound.
Trees don’t heal like people. When a cell is damaged, a tree cannot go back and fix or replace it. But it can limit the damage by containing it and excommunicating it from the rest of the still-growing tree. The trick is in sealing, not healing. The focus is on resisting the spread of damage – especially infections of bacteria and fungi and the decay they cause – by isolating the wound and then growing beyond it.
We cover a cut with neosporin and cover it with a bandage, but this is NOT helpful to a tree. Tree paint or tar or other “pruning dressings”– while a great temptation to tree lovers everywhere – actually interferes with the normal progression of a tree’s wound response and should be avoided.
Many such products are petroleum or even asphalt based and may hold moisture, mildew, and fungus against a wound without letting it dry out.
Trees need to seal and close, and generally they do this much better without additives.
What to prune?
•Remove branches that rub together.
•Remove any downward-growing branches.
•Remove branch stubs
•Remove branches that grow inward
•Avoid topping trees. Never prune the leader.
•Remove diseased or dead branches.
•Remove Narrow-angled branches - most likely to split
•If two limbs are crossed, entangled or otherwise competing, remove one of them completely at its base.
•Remove any limbs along the trunk that are bigger in diameter than the trunk.
•Remove suckers coming up from the roots or low on the trunk.
•Remove those crazy vertical branches that aren’t the main leader - “watersprouts”
•Remove “suckers” (like water sprouts but coming up from the roots) both suckers and watersprouts have weak connections to the old wood.
The Goal
•Appearance in the landscape is essential to a plant's usefulness. For most landscapes, a plant's natural form is best.
•Avoid shearing shrubs into tight geometrical forms unless they need to be confined or trained for a specific purpose.
•When plants are properly pruned, it's hard to tell that they've been pruned.
The Right Tools
•Sharp tools are safe tools
•A good pair of pruning shears is probably one of the most important tools. Cuts up to 3/4 inches in diameter.
•Loppers are long handled pruning shears with greater leverage for branches up to 1½ inches in diameter.
•Hedge shears are meant only for pruning hedges, nothing else. They cut small stems best.
•Hand saws are very important for cutting branches over 1 inch in diameter. Many types of hand saws are available. Special tri-cut or razor tooth pruning saws cut through larger branches – up to 4 inches in diameter – with ease.
•Pole saws and loppers allow for extended reach with a long handle.
•Chain saws - Operators must wear protective clothing and exercise caution when using them. Never use chainsaws to reach above your shoulders, or when you are on a ladder.
Changing Southern California with Trees
Trees and vegetation lower surface and air temperatures by providing shade and through evapotranspiration.
Shaded surfaces may be 20–45°F cooler than unshaded
Evapotranspiration can help reduce peak summer temperatures by 2–9°F
Trees (especially fruit trees) can fireproof a region. - Easy Fire hit avocado orchards and stopped cold
Benefits and Costs
• Reduced energy use: Shade decrease demand for air conditioning.
• Improved air quality and lower greenhouse gas emissions They also remove air pollutants and store and sequester carbon dioxide.
• Enhanced stormwater management and water quality: Vegetation reduces runoff and improves water quality by absorbing and filtering rainwater.
• Reduced pavement maintenance: Tree shade can slow deterioration of street pavement, decreasing the amount of maintenance needed.
• Improved quality of life: Trees and vegetation provide aesthetic value, habitat for many species, and can reduce noise.
For those who want to save $$$ and not the environment …
• The primary costs of maintaining trees or other vegetation include purchasing materials, initial planting, pruning, pest and disease control, irrigation.
• A five-city study found that, on a per-tree basis, the cities accrued benefits of $1.50–$3.00 for every dollar invested in trees.
• Personal financial benefits: Well established that good landscaping has a 110% ROI. HGTV reports that several recent nationwide surveys show mature trees in a well-landscaped yard increase the value of a house by anywhere from 7% to 19%.
• Median home price of $550,000. 7% = $38,500. 19% = $104,000. So … the best ROI on your home is to buy a giant $15,000 specimen tree because it will double in value as soon as it's in the ground.
Keyword - Dormancy
Happens to ALL trees - tree rings prove it
What causes changing colors of leaves?
Chlorophyll production (green) is shut down and absorbed back into the tree (look at changing leaf and you’ll see green in the veins).
Carotenoids (sunblock) begin to show through.
Anthocyanins produced in autumn (protect against being eaten).
Once the leaf has been drained of it’s chlorophyll the stem is sealed off and drops.
Dormancy means tree experiences less shock because it’s not trying to produce - Like being in twilight sleep at the dentist.
Pruning
Don’t top trees!
Mutilates the graceful gradual tapering of branches
Doesn’t shorten a tree
Does make it unhealthy and unstable
How to prune
Clear out internally facing branches and lift edges of canopy
Cut back cracked/damaged branches for wind and rain
Don’t trim flush with trunk or leave too long - 3 Cuts
Find the “branch collar”or “bark collar” where smooth branch and trunk bark meet.
Start with a relief cut underneath about 2’ off trunk and ¼ of the way through - to keep branch from cracking and peeling into trunk bark
Cut branch through a foot or so above relief cut
Cute remaining stub at branch collar line.
Properly healing tree makes a trunk lump and starts with a bark doughnut.
Planting
Old gardening axiom that says the key to growing a great plant is to put a 50-cent specimen in a $5 hole.
Hole should be depth of the root ball (to prevent settling) and 3 times the width
Soil amendments have limited effect, so just put the soil back in the hole, loosely packed, and use the extra for a watering berm
Water soon after planting and every day for several weeks afterward. Deep water {from at least 2 sides to bottom of hole via watering steaks or drainage pipe.
Gradually reduce the frequency of watering.
Fertilizer is also of marginal benefit at planting time, and can even be harmful, so wait until the following year.
A 3-inch layer of mulch around the base of the tree will keep weeds out and reduce water loss.
Stake your tree - steaks should go 2’ deep. 2 or 3 stakes at slight angle in toward tree. Tie loosely enough that tree won’t blow over but can sway enough to develop it own support roots.
Mulch
Mulch is … any material spread over the surface of the soil as a covering.
Retains moisture in the soil, suppresses weeds, keeps the soil cool in summer, warm in winter. Organic mulch improves fertility as it decomposes.
Mulch is not compost, but compost can be used as mulch.
Feed
Slow release fertilizer - favorite: soil builders like worm castings
Water
Roots grow toward water - water deep & regular - ultimately trees will find their own
Protect
Prevent gnawing by critters looking for nest bark wounds and wrap trunks in no traction collars