Best Time To Trim Oak Trees + Trimming Calendar And Tips

Today we’re talking about the best time to trim oak trees. Did you know trimming oak trees at certain times can be detrimental to your tree?

Oak trees respond best to trimming in the winter and early spring. Dates between October 1st and April 1st will usually provide optimal oak tree trimming conditions. This is because the tree, and potentially damaging fungi, are dormant, making your oak tree less susceptible to damage and disease.

Read on to learn about the best time and season to trim your oak trees. Did you know that there’s an optimal time to trim your oak trees? We’ve got you covered with a trimming calendar and the best zones for growing oak trees.

Here are our tips on general oak tree tips and the best time to trim oak trees.

The Best Time To Trim Oak Trees

Oak trees are commonly found throughout the world in temperate regions and even some tropical regions. Oaks belong to the genus Quercus, which consists of 400 species and are both deciduous and evergreen.

Oaks contain tannic acid, which helps in protection from fungal diseases and insect infestations. Although oak trees contain tannic acid, they are susceptible to a variety of diseases caused by both fungus and insects.

Oak trees are extremely susceptible to a handful of diseases, including sudden oak death and oak wilt. Both of which kill oak trees quickly. To avoid this, trim oak trees when the trees are dormant. 

If you are looking for a new tree trimmer, the Greenworks 40V 8-inch Cordless Pole Saw is a fantastic option! It has a 20-inch steel blade and an automatic oiler for peak efficiency!

The best time to trim oak trees is in the winter and early spring, preferably after October 1st and before April 1st. When your oak tree is dormant, the tree is not actively growing. Pruning trees during this time will limit and prevent the spread of fungal and insect infestations. 

Similarly, during winter, fungi and insects are dormant, so it is significantly less likely to spread diseases during this time..

Common Oak Tree Diseases That Happen From Trimming

You would think tannic acid would prevent oak trees from getting most diseases, or at least protect them. However, this is not the case. 

Some of the most significant and fatal diseases to oak trees include sudden oak death, Phytophthora ramorum, and oak wilt, Bretziella fagacearum. Both sudden oak death and oak wilt are diseases caused by mold and fungus, despite tannic acid being present. 

Sudden oak death, Phytophthora ramorum, is a water mold, or an oomycete, meaning it produces a motile zoospore. Motile zoospores can move towards and away from certain chemicals, i.e. food source chemicals, specifically in plant material. 

According to the USDA’s Animal and Plant Health Inspection Service, reports of sudden oak death began in 1995, and it is considered an invasive exotic species. Sudden oak death was first detected in San Francisco, California, and in Oregon, both of which have the exact climate this pathogen thrives in. 

This oak tree ailment can also affect over 75 different plant species, contributing to its spread. P. ramorum spreads through rain, contaminated irrigation or plants, and even contaminated soil. It creates calluses, also known as cankers, on the bark seeping black and red. 

Oak wilt, Bretziella fagacearum, is a fungal disease that rapidly kills thousands of oak trees every year. Unfortunately, oak wilt spreads to newly pruned trees in spring and summer. Fungal spores spread by attaching themselves to insects such as beetles that bore into the wood, and through firewood transportation by humans. 

Oak wilt can also be spread long distances via airborne spores and shorter distances via root systems beneath the ground. Oak wilt is a vascular wilt disease that prevents water from getting to the rest of the tree. 

As if this wasn’t bad enough, the fungus can overwinter on dead tissues on trees appearing in spring and summer, killing the tree within two months. 

Symptoms of oak will consist of exactly what the name states, wilting. Leaves may wilt and become discolored, resulting in defoliation, i.e., sudden leaf drop. There is currently no treatment for this disease, but arborists are working to conserve oak trees and limit the spread of this disease.

To learn more about all the common oak tree ailments, read our guide: What’s Wrong With My Oak Tree? 10 Most Common Oak Diseases.

Oak Tree Trimming Calendar By Name And Hardiness Zone

Tree Name	Best Time To Trim	Best Growing Zone
White oak, Quercus alba	Winter/Early Spring	3-9
Willow oak, Quercus phellos	Winter/Early Spring	5-9
Swamp white oak, Quercus bicolor	Winter/Early Spring	3-8
Northern pin oak, Quercus ellipsoidalis	Winter/Early Spring	4-7
Scarlet oak, Quercus coccinea	Winter/Early Spring	4-9
Bur oak, Quercus macrocarpa	Winter/Early Spring	3-8
Swamp chestnut oak, Quercus michauxii	Winter/Early Spring	5-9
Pin oak, Quercus palustris	Winter/Early Spring	4-8
English oak, Quercus robur	Winter/Early Spring	5-8
Red oak, Quercus rubra	Winter/Early Spring	4-8

Species Of Trimmable Oak Trees And Where They Grow

White Oak Tree, Quercus alba

The white oak is a deciduous oak found in zones 3-9 and is native along the east coast of the United States, found as far north as Maine and south to Florida, and as far west as Minnesota and Texas.

We typically use white oak trees for timber and flooring. This oak species grows from 50 to 80 feet tall and even as tall as 100 feet!

You can learn more about white oak trees in our article: 32 Incredible Facts About White Oak Trees.

Willow Oak Tree, Quercus phellos

The willow oak is also a deciduous oak found in zones 5-9. This oak tolerates poorly draining acidic soils, and covers from East Coast to Midwestern United States. The willow oak typically grows anywhere from 40 to 75 feet, along the bank of swamps, streams, or canals.

Swamp White Oak Tree, Quercus bicolor

Swamp white oak trees are deciduous oak trees found throughout zones 3-8. It needs acidic wet soil but is also drought tolerant. 

Swamp white oak trees also grow at a slow to average rate and are native as far north as Southern Canada to the Midwestern United States. The swamp white oak gets as large as 50 to 60 feet and grows along the banks of swamps, lowlands, floodplains, lakes, and valleys.

Northern Pin Oak Tree, Quercus ellipsoidalis

The northern pin oak is a low-maintenance oak tree found in zones 4-7. This oak reaches a height of 50 to 70 feet and is drought tolerant, growing well in acidic and well-draining soils. 

This oak is a medium-sized deciduous oak with elliptical green leaves. This oak species lives from Canada to the Midwestern United States in sandy upland woods.

Scarlet Oak Tree, Quercus coccinea

The scarlet oak grows in zones 4-9 within the eastern part of the United States and is native to Missouri. It tolerates drought conditions and black walnuts and grows to 70 feet tall. 

Bur Oak Tree, Quercus macrocarpa

Bur oaks are native to Missouri and grow in zones 3-8. Although it prefers moist loamy soils, it can also withstand a variety of soil conditions. 

Bur oak trees grow in stream valleys like the Ozark in Missouri and bottomland soils.. This species of oak grows to a height of 60 to 80 feet tall and gets its name from the ring of mossy burrs found around the acorn.

Swamp Chestnut Tree, Quercus michauxii

Swamp chestnut oaks grow mainly in the southeast of the United States, and zones 5-9. This species is native to swampy areas, floodplains, and lowland wooded areas. 

Swamp chestnut oak trees reach heights of 40 to 60 feet and were traditionally used as a timber tree in the 1800s. The people of this time used it in flooring, wagons and tools, as well as baskets.

Pin Oak Tree, Quercus palustris

The pin oak is a medium-sized deciduous tree that grows in zones 4-8. It grows well in medium to wet acidic loamy soil, but can also tolerate poorly draining soils. 

However, pin oaks do not do well in alkaline soils. Pin oak trees grow anywhere from 50-70 feet and thrive in the lowlands of the Midwest. Some people commonly use pin oak trees as landscape trees and along streets.

English Oak Tree, Quercus robur

According to Nazareth College Plant Biology, English oaks are native to Western Asia and Europe, but were introduced to North America in the 1600s and came to use as timber in England. These trees grow anywhere from 40 to 70 feet and grow easily in a variety of soils, typically growing best in zones 5-8.

Red Oak Tree, Quercus rubra

The red oak, also called the northern red oak, is a deciduous oak tree found in zones 4-8 and is native to Missouri. This species of oak tolerates drought conditions, black walnuts, as well as air pollution. This is a fast-growing oak tree that reaches a height of 50 to 75 feet tall.

You can learn more about the red oak tree in our piece: 29 Incredible Facts About Red Oak Trees

Hardiness Zones Where Oak Trees Grow

You will find oak trees throughout North America and grow in almost every zone. They are most common in temperate regions like the United States, but also grow in Mexico, Asia, Europe, and even Africa.

According to the University of Idaho College of Natural Resources, various oak tree varieties grow throughout zones 2-9. With over 400 oak tree species, you can find oak trees in almost every environment. Oak trees thrive in a variety of soils from acidic to alkaline and from clayey to sandy.

In these hardiness zones, there are specific varieties that can grow in sub ranges of the parent range described above which we’ll discuss below! While trimming in these zones is best during the winter/early spring season, you can learn more about the best time to plant oak trees in our article: The Best Time to Plant an Oak Tree (And How to Do it)

Common Uses Of Full Grown Oak Trees

Oak trees are famous for their incredibly sturdy and long-lasting wood. For more commercial goods like fence posts, cabinets and floors, we use red oak. White oak is a durable wood that is used in furniture, to make barrels, canoes, and fence posts. Oak is great for construction and woodcarving because of its durability. 

Oak flooring comes from red and white oaks and is the most common wood flooring that allures people with its tight-knit grain you can stain in an array of colors. Oak flooring is probably the most wide-known use of oak that gives a timeless look to homes.

Some oak species have also been used in natural pharmaceuticals because of their anti-inflammatory and antibacterial properties from tannins found naturally in oak bark.

Historically, Native Americans used parts of the red oak and white oak to treat ailments and wounds. The oak tree is also sacred and used in ceremonies in certain Native American cultures. 

Acorns have been used to create flour, soups, and other types of foods. In traditional medicine, it has been used to treat hemorrhoids, diarrhea, ulcers, and wounds. Today, you can find oak bark sold over the counter as powders, teas, and liquid extracts.

Learn more about the uses of oak trees and what types are best for firewood here!

Best Time To Trim Oak Trees: In Conclusion

That’s all we have for today on the best time to trim oak trees, oak trimming calendar, and tips. If you have ever walked down a street with trees, gone for a hike, or hung out in a backyard, it’s a safe bet that you’ve seen an oak tree! Oak trees are widely beneficial to the ecosystem and provide us with a variety of things that are part of our everyday life.

To recap, here are the best times to trim oak trees, and a quick list of some tips: 

• The best time to trim or prune oak trees is in the winter when insects, fungus, and trees are dormant
• Oak trees are susceptible to devastating diseases like sudden oak death and oak wilt
• Oak trees grow in zones 2-9 throughout the world
• Oak trees can tolerate a variety of soils and environments
• We covered only 10 species of oak trees, but there are over 400 species of oak trees.
• We use oak trees for timber, construction, hardwood flooring, cabinets, and furniture. Traditional medicine and Native American cultures also find oak trees useful.

There you have it. Oak trees are incredibly durable yet simultaneously susceptible to rapidly spreading fungal diseases. They make up our deciduous forests and provide us with timber we use to build homes, furniture, and flooring. Next time you think about pruning your oak tree, refer to this article and keep in mind to only trim it in the winter!

If you’re finding that your oak tree has been affected by early trimming, read our guide: 10 Early Symptoms of a Dying Oak Tree: Prevention Guide

References:

Juice, S. M., Templer, P. H., Phillips, N. G., Ellison, A. M., & Pelini, S. L. (2016). Ecosystem warming increases sap flow rates of northern red oak trees. Ecosphere, 7(3), e01221.

Rose, Anita K., Cathryn H. Greenberg, and Todd M. Fearer. “Acorn production prediction models for five common oak species of the eastern United States.” The Journal of Wildlife Management 76.4 (2012): 750-758.

Taib, Mehdi et al. “Medicinal Uses, Phytochemistry, and Pharmacological Activities of Quercus Species.” Evidence-based complementary and alternative medicine : eCAM vol. 2020 1920683. 31 Jul. 2020, doi:10.1155/2020/1920683

Vettraino, A. M., et al. “Occurrence of Phytophthora species in oak stands in Italy and their association with declining oak trees.” Forest Pathology 32.1 (2002): 19-28.