Spruce Tree Trimming Guide: How To Prune Spruce Trees To Reduce Disease

Spruce tree trimming is an important practice that not only helps keep your trees healthy and beautiful but also reduces the risk of disease.¹⁰

Spruce trees are a popular choice for landscaping trees due to their striking pyramidal form, interesting texture, and year-round greenery. However, without the occasional Spruce tree trimming maintenance, your Spruce trees can become misshapen, overgrown, and susceptible to unpleasant conditions.

Properly trimming your Spruce trees, among other evergreens,¹⁴ allows more air circulation and sunlight penetration, encourages fuller growth, removes diseased or damaged branches, and helps reduce the spread of infections.

In this comprehensive Spruce tree trimming guide, you will learn the key reasons for trimming Spruces, when and how to trim Spruce trees, the Spruce trimming process based on tree size, tips on hiring an arborist or tree trimming service, and understand the desired results of trimming.

With the right tools and techniques, you can properly and effectively trim your Spruce trees to promote health and reduce disease.

Spruce Tree Trimming: Signs Your Spruce Tree Needs Pruning

Although pruning has its benefits, you should only prune your Spruces when it is necessary.

Watch out for these signs that your Spruce tree needs corrective pruning:¹⁴

• Dead, limp, yellowing, or browning needles
• Broken, split, or hanging branches
• Mushrooms or fungi growing on bark
• Resin bleeding from branches
• Crossing, rubbing branches
• Lopsided or asymmetrically shaped tree

If these symptoms are present, it might be time to trim the Spruce to improve health and structure.

The Process of Trimming Spruce Trees (How To Prune Spruce Trees Based on Size)

Trimming your Spruces on your own requires you to have a clear objective.

Additionally, it is important to note that the trimming process differs slightly depending on the size and age of your Spruce trees.⁸

Tools You Need For Trimming Spruce Trees

You need to have these basic tools on hand for Spruce tree trimming:¹²

• Bypass pruners: Sharp, clean bypass pruners make quick work of smaller branches up to 1⁄2-inch diameter.
• Loppers: Long-handled loppers extend your reach for branches up to 1 1⁄2 inches thick.
• Hand saw: A curved hand saw tackles thicker branches that pruners can’t handle.
• Pole saw: A pole saw or pole pruner is useful for high branches out of reach.
• Safety gear: Wear thick gloves, long sleeves, and eye protection when pruning. Spruce branches can whip back and the needles are sharp.
• Disinfectant: For sanitizing tools between cuts on diseased trees
• Trash bags or tarps: For collecting and removing debris

How To Trim Small Young Spruce Trees

For young and small Spruce trees under 10 feet tall, hand pruning is often sufficient to maintain their naturally conical form but you can use gardening tools as needed.

(Image: F. D. Richards¹⁵)

The goal when pruning young trees is to:

• Remove competing leaders
• Head back overly long branches
• Eliminate narrow crotch angles
• Thin inner branches

To trim young and small Spruce trees, follow these tips:

Supplies Needed:

• Bypass hand pruners (or scissor-action pruners for smaller branches)
• Loppers for branches over 1/2-inch diameter
• Sterilizing spray or wipes
• Trash bags or tarps for collecting and removing debris

Pruning Steps:

1. Sterilize tools before use with a disinfectant spray or alcohol wipes to prevent transmitting disease between branches.
2. Remove all dead, dying, broken, and diseased branches. Make cuts just outside the swollen branch collar.
3. Identify branches that rub together, grow downward, or look out of balance. Remove these back to a bud or lateral shoot facing the outside of the tree.
4. Cut back excess height on upper branches and leader stems to maintain a pyramidal outline. Aim for outward-facing buds.
5. In spring, pinch back new candle growth by hand, removing 1/3 to 1/2 when needles are still tucked tightly.
6. Remove invasive water sprouts (vertical shoots from the trunk) and prune competing leaders to one dominant stem.
7. Monitor for regrowth in summer and make additional corrective pruning cuts as needed before new needles harden off.

How To Trim Large Spruce Trees

For Spruce trees over 10 feet tall, pole saws and loppers allow safe, proper pruning of upper branches. When trimming large mature Spruces, the goal is to:

• Remove deadwood
• Shorten overextended branches
• Thin congested areas
•  Lift up the canopy
• Restore damaged leaders

Supplies Needed:

• Hand pruners (bypass type)
• Loppers for lower branches
• Pole saw/pruner for high branches
• Sterilizing spray or wipes
• Trash bags or tarps for collecting and removing debris

Pruning Steps:

1. Clean and disinfect all pruning tools before making cuts. Wipe down the pole saw between branches.
2. Start by removing all dead branches first. Cut back damaged, crossing, and congested branches to lateral shoots or buds.
3. Identify the central leader stem. Remove vigorous vertical shoots growing up off the main trunk.
   Also, remove competing leaders so one main stem remains.
   Storm damage or other injury to the central leader requires prompt restorative pruning. Stabilize the best lateral branch as a new leader using splints or ties.
4. Head back upper branches and leader stems using the pole saw. Aim for outside buds to maintain a pyramid shape.
5. In spring, pinch back new candle growth using a pole pruner or ladder when accessible. Remove 1/3 to 1/2 of length.
6. Monitor for water sprouts and dense interior growth throughout summer. Remove as needed until the needles harden off.

How To Make Proper Pruning Cuts on Spruce Trees

Where and how you make pruning cuts on Spruce trees is critical.¹ Below are the cuts you can safely make on your Spruces:

Collar Cuts

When removing entire branches, cut just outside the branch collar (the swollen joint where the branch attaches to the trunk) making sure you do not leave a stub or any damage on it.

Angle your cuts away from any remaining stem tissue.

Heading Cuts

Make heading cuts on upright shoots above an outward-facing bud. Cut at a 45-degree angle above the bud to direct new growth.

Thinning Cuts

Thinning cuts remove a branch back to its point of origin or attachment, such as back to a larger branch or the trunk.

Avoid flush cuts directly in line with the remaining stem. Also, make sure you do not injure the branch collar. For larger branches, use the three-cut pruning method.³

Three-Cut Method for Large Branches:

1. About 12-15 inches from the trunk, make an undercut halfway through the underside of the branch to prevent bark tearing when the limb falls.
2. A few inches past the undercut, make a second cut down through the top of the branch removing most of its weight. The branch breaks free leaving a short stub.
3. Make a final cut just outside the branch collar to remove the stub. Avoid cutting into or damaging the branch collar.

For pole saw pruning,¹ start with cut #1 about 6-10 inches from the trunk, followed by cut #2 and #3 in sequence as described above.

Tips for Proper Pruning for Spruce Tree Health

In addition to technique, proper sanitation, timing, and prevention help ensure that pruning actually improves the health of your Spruce trees.⁷ The tips below should help:

• Disinfect pruning tools before and after each branch or tree with a household disinfectant, bleach solution, or alcohol to prevent the spreading of disease.
• Prune during dry weather conditions to reduce disease entry. Avoid pruning just after rain or heavy fog.
• Seal wounds over 2 inches in diameter with non-toxic tree wound paint or shellac to protect them from insects and infection while healing.
• Remove all debris and dead needles under the tree after pruning to prevent fungal inoculum from splashing back onto branches.
• Monitor for damaged branches, fungi (like Cytospora canker), and signs of insects. Prune and treat issues immediately to maintain vigor.
• Prevent over-pruning that stresses trees, slows growth, and provides entry points for pathogens. Never remove more than 25% of living foliage in a season.

Spruce Pruning Mistakes To Avoid

Improper pruning cuts and techniques can damage Spruce trees. Here are some common pruning mistakes to avoid:⁴

• Topping: Never remove the central leader of Spruce trees unless it is severely damaged or diseased. This destroys the tree’s natural form.
• Over-thinning: Removing too much inner foliage starves the tree of energy production.
• Excessive heading: Repeated heading causes congestion. Make thinning cuts to open up the interior.
• Pruning into old wood: Don’t cut back farther than the green needles. Spruces won’t generate new growth from old, bare branches.
• Flush cuts: Pruning too close parallel to the trunk damages the protective bark and the branch collar.
• Painting cuts: Although popular, tree wound paints interfere with the tree’s natural compartmentalization. Allow the wounds to seal over naturally.
• Pruning in fall: Late summer or fall pruning risks new growth being winter damaged.
• Skipping sanitation: Failing to sanitize tools between cuts allows disease transmission across branches and trees.

When To Trim Evergreen Bushes Like Spruce

Timing is important when trimming all types of evergreen trees like Spruce. The idea is to prune in line with the natural growth patterns of your trees.⁶

To achieve the best results, trim at these times:

Early Spring (Before New Growth)

You can safely prune your Spruces in early spring before or just as buds begin to swell and new growth starts emerging. The cuts typically heal quickly as trees direct energy into developing shoots.

You can remove dead wood, shape wayward branches, and make preventive thinning cuts at this time.

Mid to Late Spring (During Candling)

As new shoots appear in spring, prune back the tender current season growth or “candles” by 1/3 to 1/2 when needles are still tightly packed.

Pinching by hand avoids damaging the needles. This will promote fuller branching in the following year.

Early Summer (New Growth Hardening Off)

When new growth begins hardening off in early summer, you can finish any reshaping or removal cuts. However, avoid pruning once candles have fully elongated and needles expanded to prevent dieback.

Fall to Winter (Dormant Season)

From late fall until just before spring growth, Spruces enter dormancy. During this time, minor maintenance pruning is feasible but be sure to avoid major reshaping that could stimulate growth susceptible to winter damage.

(Image: Nicholas A. Tonelli¹⁶)

Avoid pruning from mid to late summer, the worst time to prune trees, when cuts may initiate new growth before fully hardening off. Additionally, needles and shoots damaged by winter cold often turn reddish-brown the following year.

Why Trim Evergreen Trees Such as Spruce?

There are several beneficial reasons for trimming Spruce trees and other evergreens:⁸

Reduce Disease Risk

Pruning out dead, diseased, or damaged branches eliminates entry points for pests and pathogens. Proper sanitation cuts that remove infected wood can stop the spread of fungal diseases like Cytospora canker.⁹

Increase Light and Air Penetration

Thinning the inner branches opens up the canopy to more sunlight and airflow. This reduces moisture levels which can lead to fungal issues.

Increased light and air can also improve fruiting and flowering on ornamental varieties.

Improve Structure and Form

Trimming back errant branches helps maintain the classic conical shape of Spruce trees. Selectively removing branches that compete with the central leader or grow at odd angles sculpt a balanced, pyramidal form and helps you retain the tree’s structure and form.

Remove Hazards

Pruning eliminates branches that overhang structures, impede lines of sight, or pose fall risks. It helps prevent limb breakage from wind, snow, and ice loads that could cause serious injuries to you, your family, or your guests.

Cutting low-hanging branches also facilitates lawn maintenance beneath the tree.

Stimulate New Growth

Heading back overextended branches triggers new bud growth farther down the stem. This results in a fuller, denser appearance over time.

However, be sure not to over-thin the crown as this might have the opposite effect: your tree might die out or stall.

When Should You Contract an Expert? (Hiring an Arborist or Tree Trimming Service)

Spruce tree trimming is a fairly easy and straightforward endeavor that you can perform by yourself if you have the right tools. However, be sure to employ the help of a qualified arborist or tree trimming service if:²

• The branches exceed your pruning equipment’s capacity which is typically trees over 15 feet tall with large branches more than 3 inches in diameter.
• Major corrective pruning is needed for storm damage, disease, or years of neglect
• Utility lines run through the tree and require clearance pruning
• Multi-stemmed trunks or other hazards put you at risk on a ladder

While you’re at it, also make sure to check a tree trimming cost calculator so you can have an idea of the cost of arborist and associated expenses in getting your Spruce tree pruned.

Benefits of Professional Spruce Tree Trimming

There are several benefits of hiring arborists or a professional tree trimming service:¹¹

• Proper identification: Arborists will properly identify Spruce species and anatomy to make informed pruning decisions.
• Risk assessment: Arborists will evaluate defects, disease symptoms, and hazards to determine priority pruning needs.
• Large equipment: Their large bucket trucks, cranes, and pole saws will facilitate pruning tall, mature Spruce trees.
• Training: Their extensive training and regular continuing education ensure proper pruning techniques.
• Insurance: Licensed, insured professionals will cover damages if an incident occurs.
• Consultation: Arborists provide seasonal maintenance schedules and long-term pruning plans.

Considerations When Hiring an Arborist To Trim Spruce Trees

Choosing the right professional pruning assistance is also important.² Look for the following:

• Certified arborists licensed in your state to ensure proper training and expertise
• Check for membership in professional organizations like the ISA (International Society of Arboriculture) or TCIA (Tree Care Industry Association)
• Look for current insurance certificates for general liability, property damage, workers’ compensation, and auto coverage
• Read online reviews and talk to neighbors for referrals to find reputable local tree companies
• Get multiple quotes and ask questions about methods, timing, clean-up, and post-care recommendations
• Inspect previous pruning work to evaluate the quality of cuts, tree health, and aesthetics
• Clearly communicate your goals for pruning and expectations for preserving tree shape and form
• Get all bids, contracts, work timelines, and payment terms in writing. Avoid making a  pre-payment.
• Ask about follow-up care, monitoring for disease, and post-pruning fertilization if needed

It is always wise to employ the help of professionals when trimming large, old, or diseased Spruce trees; let professionals handle riskier complex pruning tasks.

Desired Results of Spruce Tree Trimming

There are various reasons you may decide to trim your Spruce trees in order to achieve a specific desired result.⁴ These reasons can change from year to year or even from tree to tree.

Below are some desired results of trimming Spruce trees:

• Improved tree health: Allowing more air, sunlight, and reduced disease for greater vigor
• Enhanced aesthetics: Pruning to minimize defects and improve structure and aesthetics
• Increased fruit/flowers: Improved light penetration to improve flowering and cone production
• Easier maintenance: Improving access for clearing and equipment beneath trees
• Reduced risk: Removing weak or defective limbs prone to breakage
• Faster growth: Invigorating new growth through moderate crown reduction
• Younger appearance: Restoring a youthful appearance in old trees through rejuvenation pruning
• Greater value: Adding property value through well-maintained trees as compared to unkempt trees

Regular and proper pruning is the key to achieving these desirable results for your Spruce trees.

(Image: USDA Photo by Lance Cheung¹⁷)

Following proper Spruce tree trimming techniques, like those outlined here, will go a long way toward having healthy, vigorous trees that resist disease.

Be sure to prune regularly, never removing too much living wood at once. With the right Spruce tree trimming approach and tools, you can prune your Spruce trees to reduce disease and promote health.

Frequently Asked Questions About Spruce Tree Trimming