Trimming the bottom of a cedar means taking off whole lower branches back at the trunk, not shearing their tips. Done well, it lets you walk, mow, and see under the tree without slowing it down. The cut itself is simple, but where you place it and how you handle a heavy limb decide whether the trunk seals the wound cleanly or invites decay.
How High You Can Safely Remove Branches
The inside of a cedar’s lower branches is often brown and bare, a dead zone where needles no longer grow. Cedars and junipers don’t sprout new foliage from that bare wood, so a branch cut back into it stays bare. A trimmed branch end will fill in with some new green growth where it was cut, but it won’t regrow its original shape.1Ask Extension. Will mature red cedar trees push end branch growth outside the dead zone after light pruning? – Ask Extension That’s why removing a whole lower branch at the trunk usually looks better than cutting it halfway back to a bare stub.
Taking off low limbs, which is called limbing up, doesn’t stunt a tree when you keep it modest. Young eastern redcedars with their lower trunk branches removed grew just as tall as unpruned trees.2Western Journal of Applied Forestry. Impact of Pruning Eastern Redcedar (Juniperus virginiana) After more than 10 years, though, trees limbed to about 2 to 4 feet had slightly thinner trunks at the base than unpruned ones.3Western Journal of Applied Forestry. Impact of Pruning Eastern Redcedar (Juniperus virginiana)
Raising the crown too high pushes the tree’s weight farther from the ground, which strains the base and raises the chance of failure in storms.4Arboriculture & Urban Forestry (AUF). Pruning Affects Tree Movement in Hurricane Force Wind So a common arborist guideline is to keep live branches on at least the top two-thirds of the tree’s height.
Start by measuring what you actually need: mower clearance, a walkway, or a clear line to a window. On a 15-foot tree, two-thirds live crown means bare trunk no higher than about 5 feet. If you only need 3 or 4 feet of clearance, removing the lowest one or two whorls of branches is often enough. Take a little at a time and step back to look, since you can’t put a branch back. Hedge-style arborvitae screens lose their privacy if the bottoms are raised, so they are better left full to the ground.
If a tree needs heavy raising, remove a few branches per year rather than all at once. Taking too much foliage in one go stresses the tree and draws down its food reserves.
Where to Make Each Cut
The branch collar is the slightly swollen ring of bark where a branch joins the trunk. It produces the new wood that grows over a cut,5Washington State University Extension. Pruning Woody Landscape Plants so cutting just outside it gives the tree its best chance to wall off the wound before decay starts.6Washington State University Extension. Pruning Woody Landscape Plants Leaving the collar intact also protects the tree from repeated attacks by disease and insects.7Research Guides. Proper Pruning of Trees and Branches: Home8Research Guides. Proper Pruning of Trees and Branches: Home
Two wrong cuts are common. A flush cut tight against the trunk slices off the collar and leaves a wound the tree struggles to close. A long stub left beyond the collar can’t be covered by new wood and tends to rot back into the trunk.
On a cedar, look for a slight bulge or wrinkled ridge of bark at the base of the branch. On small branches the collar may be subtle, so cut just beyond where the branch starts to flare. Angle the cut slightly down and away from the trunk, following the collar’s outer edge. A good cut leaves a round, coin-shaped wound rather than a long oval. The same collar rule applies at every size, including pencil-thin branches and dead lower branches.
Months later, a doughnut-shaped ring of new wood should be rolling in from the edges of the cut. Peeling bark or dark oozing around a cut is damage worth watching.
The Three-Cut Method for Heavier Branches
A heavy branch cut from the top in one go can fall partway through and peel a strip of bark down the trunk.9Leaf & Limb. How to Prune with the 3-Cut Method That torn wound leaves the tree open to wood-decay fungi and can even kill it.10Leaf & Limb. How to Prune with the 3-Cut Method The three-cut method prevents it:
- First cut: saw upward from underneath, about 2 to 3 inches out from the collar, partway through the branch.11Leaf & Limb. How to Prune with the 3-Cut Method This undercut stops bark from ripping down the trunk when the branch drops.12UF/IFAS Extension Lake County. The 3-Cut Tree Pruning Practice
- Second cut: from the top, about 4 to 5 inches out from the collar, beyond the undercut, until the branch falls.13Leaf & Limb. How to Prune with the 3-Cut Method The first two cuts remove the weight without peeling bark, leaving a short stub.14Leaf & Limb. How to Prune with the 3-Cut Method
- Third cut: remove the stub just outside the collar, as described above.
Any branch too heavy to hold in one hand while you cut needs this method. Thinner branches can be cut once with pruners or loppers.
Stand to the side of the branch, never directly under it. Wear gloves and eye protection, since cedar foliage is prickly and sawdust flies. For branches you can’t reach comfortably, use a pole saw rather than a ladder. Call an arborist for limbs near power lines or too high to cut from the ground.
For the final cut, hold the stub with your free hand. Slow your strokes near the end so the stub doesn’t snap and tear. If any ragged bark edges remain, trim them flat with a sharp blade.
The Best Time of Year to Trim
Late winter, roughly February to March in most of the US, is the usual recommended time, while the tree is dormant. Cuts made just before spring growth begins close quickly once the tree wakes up. Cooler weather also means fewer active insects and fungal spores to reach fresh cuts.15Bunyon Bros. Tree Service. Trimming Cedar Trees: How to Trim and Prune Cedar Trees Dead or broken branches can be removed at any time of year.
Avoid heavy cutting in hot, dry summer spells, when the tree is already stressed. Late summer cutting can leave wounds open going into winter. If you’re in a drought, water the tree first and wait.
Removing one or two small low twigs is fine in any season, but save multi-branch raising for the dormant season. Frozen wood can split, so pick a mild winter day.
Tools You Need and How to Keep Them Clean
Hand pruners handle twigs up to about half an inch, loppers go up to about an inch and a half, and a pruning saw takes anything larger. Use bypass pruners and loppers, which cut cleanly like scissors rather than crushing. A carbide sharpener or diamond-coated stone keeps their blades sharp.16Orchard People. Learn how to grow and enjoy the fruit of the overlooked and forgotten medlar (Mespilus germanica)
A dull blade tears bark and crushes the tissue the collar needs. Cedar sap gums up blades, so wipe them often during a job.
Dirty tools spread disease. Pruning tools can carry fungi, bacteria, and viruses from one plant to another.17University of Arizona Cooperative Extension. Sanitizing Pruning Tools Tools contaminated with a canker fungus can pass it between trees,18HortScience. Comparative Efficacy of Sanitizers in Preventing Plant-to-Plant Transmission of Botryosphaeria dothidea via Cutting Tools in Eastern Redbud (Cercis canadensis) and shears carrying trunk fungi have infected fresh cuts that showed disease months later.19PubMed. Detection of Grapevine Fungal Trunk Pathogens on Pruning Shears and Evaluation of Their Potential for Spread of Infection Wipe blades with rubbing alcohol or a disinfectant between trees, especially after cutting diseased wood.
Keep a spray bottle of 70% rubbing alcohol in your tool kit, wipe the blade, and let it air-dry a few seconds before you continue. Oil the blades afterward to prevent rust.
Mistakes That Damage Cedars
Lion tailing is stripping the inner foliage along a branch and leaving only a tuft at the tip. It removes too much leaf area, cutting the tree’s food production and forcing it to draw on stored reserves.20Kansas Forest Service. Lion Tailing and its Impact on Tree Health With weight concentrated at the tips, branches can’t sway and are more likely to break in wind or ice.21Kansas Forest Service. Lion Tailing and its Impact on Tree Health
To tidy without lion tailing, remove whole branches at the trunk instead of stripping twigs along each one. Leave interior foliage on the branches you keep, and aim for an even, natural taper from bottom to top.
Cutting the top off a cedar to control height leaves a permanent flat-top, because cedars don’t regrow a leader well. Removing lower limbs in the same season that you shear the rest of the tree stacks stress on it.
If you hire help, ask for a certified arborist rather than a general landscaper. Ask how high they plan to raise the crown before work starts, and refuse quotes that mention topping or “cleaning out” the interior.
Aftercare and What to Do With the Branches
Skip the pruning paint. Pruning paint and wound dressings give little help and can slow healing,22Arborilogical. Should You Use ‘Pruning Paint’ On Your Trees? because covering the cut can damage the living tissue that forms the healing ring.23Arborilogical. Should You Use ‘Pruning Paint’ On Your Trees?24Extension. Should I cover large pruning wounds with a tree wound dressing? Leave cuts open to air; a correct collar cut is the real protection.
Cedar bark beetles are drawn to wounded junipers, especially ones giving off ethanol.25Western Journal of Applied Forestry. Response of bark and woodboring beetles to host volatiles and wounding on western juniper Trees under stress release ethanol,26Western Journal of Applied Forestry. Response of Bark and Woodboring Beetles to Host Volatiles and Wounding on Western Juniper so keeping wounds small and the tree well watered after heavy trimming makes it less inviting. Watch for tiny round holes in the bark or fine sawdust at branch bases. A branch whose foliage turns reddish-brown is another sign. If several branches brown at once, call an extension office or an arborist.
To help the tree recover, water deeply during dry spells for the first summer. Don’t fertilize heavily right after trimming. A mulch ring a few inches deep helps, as long as it stays away from the trunk.
The trimmings can become mulch. Some conifers, including true cedars, can release chemicals that hold back other plants in forests.27Journal of Forest and Environmental Science. Allelopathic Potential of Select Gymnospermous Trees But there’s virtually no documented evidence of that effect from cedar or arborvitae wood chips.28Washington State University. The Myth of Allelopathic Wood Chips Fresh mulches of many kinds do slow seed sprouting at first.29Arboriculture & Urban Forestry (AUF). A Comparison of Landscape Mulches: Chemical, Allelopathic, and Decomposition Properties Use cedar chips around shrubs and trees, but not on beds where you’re sowing seeds.
Limbing Up a Cedar for Wildfire Safety
Ladder fuels are low branches and brush that let a ground fire climb into a tree’s crown. Large trees with thick brush underneath are a key reason areas get high wildfire hazard ratings.30Oregon State University Libraries. Community Wildfire Protection Plan For the City of Cascade Locks Removing low branches and spacing trees makes it much harder for fire to reach the crowns,31About Trees. Tree Trimming & Pruning for Fire Prevention and Defensible Space so limbing up helps create defensible space around a home.32About Trees. Tree Trimming & Pruning for Fire Prevention and Defensible Space Cedars and junipers have oily foliage that burns readily, which makes this especially useful.
Fire guidance commonly suggests limbing mature trees to about 6 to 10 feet. You should still keep two-thirds live crown, so small trees get less raised. Clear brush and dead needles under the tree too. Defensible-space rules vary by region, so check your local fire agency’s.
A cedar right against a house is a bigger risk than trimming alone can fix. Keep branches well clear of roofs and gutters, and remove dead foliage trapped inside the canopy, which ignites easily.