Tree Care

Summer Tree Care in the Pacific Northwest

Summer sun is here! If you got a tree from us this past season, you can expect a Summer Tree Inspector to come by to see how your newly planted tree is faring if they haven’t already. Longer, hotter summers mean that even species native to this region are struggling to stay hydrated.

“Unlike in other areas of the country, like the East and the Southeast… we don’t get any rain during most of a tree’s growing season. And so as far as tree care at this time of year, I’m mostly thinking about watering.”
–Litzy Venturi, Community Tree Care Coordinator

Each summer, we try to visit every single tree that was planted during the prior planting season. Our volunteer inspectors are trained to check on these young trees to make sure they’re getting the care they need to make it through their first summer.

Here are some pointers from our Summer Tree Inspector Program for protecting your trees in the heat. You can always visit our Young Tree Care Guide if you have any questions.

  • Water and mulch
    Trees depend on water to survive the heat. A protected environment that prevents evaporation is key, giving water an opportunity to go deep and be taken up by the roots. Here’s are some steps:
  • Create a mulch donut over the roots: Apply a three-inch layer of mulch over the root zone to prevent evaporation and help water reach a little deeper. Be sure to leave a three-inch gap of bare soil directly around the trunk; keeping the bark constantly wet creates an entry point for disease.
    • Mulch helps keep weeds and grass down, which limits the need for using lawn mowers and string trimmers near the tree’s trunk. Recommend hand pulling weeds/grass. Significant bark damage can impact its ability take up water, and can ultimately shorten a tree’s life.
  • Water when it is cool: Early morning or late evening is best. Watering during the heat of the day causes the water to evaporate before it can reach the tree’s roots.
  • Water deeply and cyclically, 15-20 gallons once per week:
    1) Watering bags: Zip a green Gator slow-release bag around the trunk (or place it next to it if it doesn’t fit) and fill it once or twice a week.
    2) DIY a 5-gallon bucket: Drill a 1/8-inch hole near the bottom of a plastic bucket, set it by the roots, and fill.
    3) A trickling hose: Set your garden hose to a gentle trickle right over the root zone for about 30 minutes.

As you water, you’ll start to get a dialogue going with your tree about how it handles the heat and you’ll notice how the soil is reacting too. Every tree is different. Here are some ways to observe and improve as you go:

  • Get a feel for soil moisture: You can push a pencil about two inches deep to see if the water is making its way into the ground near your tree’s roots. If it comes out clean, this is a sure sign your soil is too dry.
  • Trees can get overwatered, especially if a tree is being watered in addition to receiving water from daily lawn irrigation. While grass takes up a lot of the water, the soil around the tree’s roots, especially when it’s young, can end up with more water than the tree can take up with its limited roots. This can kill the tree
  • Widen the watering area: You can move your watering zone a few inches farther out from the trunk each summer. This encourages roots to grow away from the trunk, which assists with anchoring and better water absorption and nutrient uptake.
  • If you can’t water: If you go out of town or otherwise leave without watering for a while, your tree might look completely parched when you get back. Compensating with too much watering without letting soil breathe can lead to rot. It is better to give your tree one deep soaking to reset the soil and then return to a regular weekly watering.
  • Build up the soil: You can put down a layer of mulch every year to replenish the donut. As it breaks down over time it feeds the tree and creates well aerated soil. Also, a wide mulch ring can help lawnmowers and weed-whackers to keep a safe distance.

“Over the course of decades, if everybody mulched their yards, we could change the city’s soil structure to be much more amenable to microorganisms and plant roots.”
–Litzy Venturi, Community Tree Care Coordinator

Look Out for heatwaves
Keep an eye on the forecast and act before the heat hits. While temperatures above 85°F are stressful for trees, you should start taking precautions as soon as the forecast nears 80°F. Also, trees in direct sun or near concrete and asphalt are especially vulnerable, as those spots get much hotter than the official forecast.

  • Pre-water: Soak the ground two days before a heatwave arrives. This gives moisture time to sink deep into the soil.
  • Remove competition: Surrounding lawn grass and plants will compete for every drop of water. Keep the tree’s root zone weeded, and you can put friendly companion plants just outside the tree’s canopy.
  • Increase water during heatwaves: Water 10 gallons per inch of trunk diameter, three times weekly during heatwaves.
  • Pay special attention to vulnerable trees: Trees with thick, waxy leaves (like white oaks or tupelos) naturally handle heat better. Trees with delicate leaves (like vine maples) will scorch much easier. Make sure these trees don’t get missed, and get extra watering.

More resources

When looking for accurate tree care information, you can check out Western-specific resources that account for dry summer climates like ours:

Tree Care

Tree Care Summer

This is what Friends of Trees gets up to between planting seasons

Our planting season is from October to April, but folks at Friends of Trees keep plenty busy in the summer. We’re planning for the season ahead of course, but we’re also checking in on the trees and native plants in the ground.

You might see our Green Space team out in natural areas making sure the native plants are properly mulched and not getting overcrowded with weeds. You might see some of our neighborhood field technicians out in the community watering trees. Or you might see some of our staff at community events connecting with folks who want to plant trees at their homes!

For volunteers, now is the time of year that our summer tree inspectors are visiting young trees to see how they’re faring. Summer Inspectors learn how to assess the health of newly-planted street and yard trees and give homeowners watering and mulching tips. Being a Summer Inspector gives you a chance to meet your neighbors and to help them take care of their trees during the critical first summer after planting.

One of the most important things inspectors check for is if a tree is getting enough water. Young trees require regular, deep watering (15 gallons, once per week). Young trees have a limited root system and can’t reach deeper into the soil to find water.

“Water is one of the three components of photosynthesis, along with sunlight and carbon dioxide, and it’s the only one we can control,” says Community Tree Care Coordinator Litzy Venturi. “Trees can’t make food without it. At minimum, a young tree won’t grow. More likely, especially in their first couple years, they’ll die without summer watering.”

Because watering is so important and we want to make sure trees survive and thrive, the BRANCH Coalition plantings have an opt-in watering service. We also work to send watering reminders to all tree recipients and helpful feedback after their trees get inspected. Think of this Treemail as yet another watering reminder! Have you been watering your tree? Check out our tree care guide for tips like the bucket method!

For trees beyond their first few years of age, summer is one of the times when it makes sense to prune. Young tree pruning is the most cost effective thing you can do for an urban forest and it’s one of the ways we make sure our trees are cared for after they’re planted. We’ve just kicked off our summer youth pruning program. At four pruning events in Portland, youth participants will get to learn the fundamentals of pruning, get hands-on practice, and get to see different parts of the city.

Tree Care

Fall Tree Care Tips

Steps to take to get your tree ready for the winter ahead

Enjoy what’s left of the fall color

Fall brings cooler days, longer nights, the return of rain, an extra layer or two when we head out, and the striking colors on display gifted to us by nature.

You’re not the only one who has felt the days getting shorter. Our trees noticed, too, and they’ve taken it as a sign that the growing season is over. How do they notice? A hormone response is triggered by the shorter daylight hours, the angle of the sun, and the cooler temps.

In a process called abscission, trees reabsorb the nutrients stored in the leaves before detaching and shedding them. Chlorophyll, which gives leaves their green color, is one of the first things to be absorbed, which is why we see them change color.

Leave the Leaves

Fallen leaves still have plenty of nutrients, which is why we encourage you to leave the leaves. Trees are putting those leaves there on purpose! We have a habit as a society to rake and dispose of leaves, but leaves are vitamins for plants and magic for building the health and vitality of soil, especially where urban soils are devoid of nutrients. Think of your leaves as free fertilizer!

You can use your leaves like mulch and rake them under your trees to nourish the roots (but keep them away from the trunk). Just like you would with mulch, follow the 3-3-3 rule: 3 inches away from the trunk, 3 inches deep, and at least a 3 foot radius. Covering the whole root zone is ideal, and the larger the tree, the wider the root zone.

Mulch for winter

Roots can grow year round in the right conditions—moisture, air, and temperature. We plant when the trees are dormant above ground so that they can focus on establishing their roots. To help keep those conditions right for your young tree, make sure you replenish your mulch for winter.

Just like mulch keeps roots cool in summer, it keeps them warm in winter. And it will protect from the drying effects of winter winds. One inch of mulch is a windbreaker, three inches is like a down jacket. Just follow the 3-3-3 rule!

Prune potential hazards

It’s a good time of year to take care of maintenance of your medium and large trees. Last winter, we saw some serious winter storms. The best thing we can be doing this time of year to make our trees more storm resilient is pruning. The combination of wind and ice can lead to branch failure—in short, nature prunes itself. That’s exactly why it’s best to prune problem areas now rather than waiting until snow and ice is predicted. Ice can increase the weight load on a branch by up to 30 times.

Now is a great time to have an arborist out to inspect your trees!

Tree Care

The Tell-Tale Soil

Inspector Intern & The Case of the Dry Leaves

by Josh Celio Espinoza

Unleashing my inner Johnny Appleseed was not on my summer schedule. I expected to spend my Communications & Business Relations internship at Friends of Trees behind a desk, researching potential business partners and monitoring social media metrics. As it turns out, that is only half the story. The other half involves filming staff gushing about their favorite trees, exploring local parks with the community, and learning how to identify native plant species with the best of them (a.k.a, my coworkers).

Recently, my job took me to the beautiful neighborhoods of southern Vancouver to inspect trees. Armed with a pencil, clipboard, and a sunny disposition, I hit the streets. From checking the moisture levels of the soil to making sure the mulch had the perfect donut shape, I had my work cut out for me. But as they say, if you love what you do, you never work a day in your life.

The goal of the Friends of Trees summer inspection program is to make sure that our newly planted trees (in their first 1-3 summers) are healthy and thriving. As a volunteer summer inspector, you’ll get to share your tree knowledge with your community, learn how to spot healthy and unhealthy trees, and ensure the survival of these young trees.

I’ve learned that, here at Friends of Trees, we don’t just plant and walk away. If a tree has dry leaves, we figure out why. Most likely, it needs more water. Mystery solved!

A tree inspector checks the branches of a tree.

 

When speaking with Litzy Venturi, our Community Tree Care Coordinator, I gathered that this program isn’t simply about inspecting newly established trees.

“A lot of these volunteers have gotten a tree themselves and by inspecting these neighborhoods, they get to form a relationship with not only the neighborhood trees, but the neighborhood itself. You get to bond with others in your community about your shared passion.”

After I took the requisite training, which only took me a couple of hours, I was assigned a route. A great aspect of this role is that you can make your hours. I picked a cool summer morning to explore my route’s neighborhood and find my new tree friends to see how they were doing.

The whole inspection process was cathartic, methodically checking each aspect of the tree for damage or irregularities. Even more than that, every house was unique in its inspection. Some had lush gardens. Others had intricate decorations all around. Only one had a large, loving cat named Biscuits, even if I wish he was at all the houses.

The one constant I found was that all these homeowners truly invested in their tree’s well-being. Everyone was delighted that their trees were being inspected, but even more so that they were doing their part for the environment. “I’ll be sure to be bright and early for your guy’s next planting,” said Catherine Ricci, a Treecipient. As I continue my internship, I realize that Friends of Trees goes beyond planting trees—they create a community invested in climate advocacy.

Tree Care

Are your trees getting enough water?

Watering tips from the Eugene Team

This July didn’t hesitate to remind us just how hot it can get in an Oregon summer, with five consecutive days with highs over 100° Fahrenheit. And while many of us are lucky to be able to find shelter from a heatwave, trees don’t have that same luxury. For young trees in particular, extreme heat can cause tremendous stress and threaten the trees’ survival.

“It’s around this time every year when we start getting a steady flow of concerns about the well-being of young trees,” says Eugene Director Erik Burke. “Trees can dry out in just a couple days in a heatwave. There are a lot of factors that go into it, including the species and the site conditions.”

Trees that are getting too much water or not enough water can show similar symptoms. Most notably, their leaves will start to brown and curl. In most instances that a tree is getting too much water, it’s because the resident has lawn irrigation systems. It’s more common that a tree is under-watered.

“It can be hard for people to apply enough water,” Erik says. “Sometimes I see people misting the ground beneath their tree with a hose and then walking away. And there wasn’t even enough water to penetrate the soil.”

Trees need deep weekly watering during hot dry summer months: 10 to 15 gallons of water around the base of the tree. It’s important to imagine where the roots are. You want the water to be reaching through the soil to the ends of those roots. It’s also good practice to water in the morning or the evening when you’ll lose less moisture to evaporation. A thick layer of mulch will help retain moisture in the soil.

During a heatwave, your tree might need to be watered more often than once a week, but how do you know if it’s time to water? You can test the soil! There are inexpensive soil moisture readers available at hardware stores, or you can use something you have readily on hand, like a pencil or a stick.

“It’s like testing a cake to see if it’s done,” says Taylor Glass, our Eugene Springfield Program Manager. Insert your pencil several inches into the soil. When you pull it back up, if soil has stuck to the pencil then it still has moisture and you don’t need to water just yet. If it comes up dry you can go ahead and water your trees. Different soil types will dry out faster than others, so it’s important to check regularly and get to know your tree’s particular site.

“Some trees will suddenly torch, that is, get really dry and stressed,” Erik says. “As soon as you see that, you just want to water the heck out of it. Every species has a different tipping point.”

Some species like the Oregon ash or California buckeye will call it quits for the year when the soil gets dried out in August and just drop their leaves. When they come back next year they’re totally fine. But other trees won’t survive.

To help new tree owners take care of their trees, Friends of Trees sends out volunteer summer inspectors. For the first three summers of a tree’s life it will get two visits. The inspector will check on the tree’s well-being, look for any issues or concerns, and check the soil to see if there’s enough moisture.

“It’s a really fun role,” Taylor says.” You get to learn about trees while walking or biking around your neighborhood.”

With heat waves becoming more and more common, we need trees and the shade they provide to keep us cool. We need to return the favor and make sure we take care of trees so that they can survive and thrive.