Water Young Trees in Summer

If you planted a tree within the last two or three years (congratulations!!!), it is still in the vulnerable stage of early root growth. Young trees need to be watered once a week, or twice a week if the weather is especially hot and dry.  The amount of water needed depends on a variety of factors including tree size and how well the soil drains.  Here are the watering guidelines in my area, from the Arlington County, VA website: 

Trees planted within the past two years that are less than 6 feet tall need a minimum of 5 gallons for each watering.  These trees should be watered at least twice a week starting in April and continuing through November.  Rainfall should not be considered adequate unless it is 2" or greater. 

The best time of day to water is early in the morning so that the amount of evaporation is minimized.  Late in the evening is the second best time.  The amount of water that comes through a hose varies for a variety of reasons such as hose size, length, size of the building's plumbing, water pressure, etc.  However, you can still estimate that about two gallons of water flow through a typical garden hose per minute.  This is roughly comparable to the amount of water that flows through the typical shower. Therefore, you should water newly planted trees for at least (3) three minutes with an unrestricted hose.  Hoses with sprinklers may need to be run longer since sprinklers may restrict the amount of water that flows each minute.

Casey Trees of Washington DC recommends "25 to Stay Alive", meaning 25 gallons per week, but the amount of water needed each week depends on the local precipitation and temperature. During the summer months, Casey Trees posts weekly tree watering recommendations on the main page of their website. Check it if you‘re unsure how much water your trees need. You can also sign up to follow them on Twitter, and that way you can receive reminders to water your trees.  If you don't live in the National Capital region, look for tree advocacy organizations in your area for information on the specific needs of the trees in your ecological region.

If you use a slow-release watering bag such as a  Treegator or an Ooze Tube, re-fill it each week from May to November.  These bags should be removed after two years. Arlington County, VA has a water truck and staff dedicated to watering street and park trees during the summer.  However, if you are within hose-watering distance of public trees that appear to be in distress, consider doing the trees and the community a favor and give the trees a drink. The watering bags can be tricky, so go ahead and visit the Treegator website for instructions. My neighbor Cheryl was motivated to fill the Treegator on the county street tree in front of her home, but it was so confusing that she wrote an article about it for our neighborhood newsletter to show others how to do it after she figured it out. Here's a link to her article, "Solving the Water Bag Mystery," in our civic association newsletter (hint, it's on page 8).

For more information on tree care, visit the TreeStewards website. Also, check out some of the great links over there to the right, such as the Tree Owner's Manual, a free downloadable, printable book from the USDA Forest Service, with everything you need to know about planting and caring for trees. =>

My Last Tree Column

I've been editing my neighborhood newsletter for two and a half years now. One of the main benefits of this job is that I've had a free forum for my native gardening and tree canopy advocacy.  I've just sent my final edition to the printer, and with it my final Tree Talk column.  Here it is:

 Tree Talk: Restoring Our Community’s Native Tree Canopy

My Last Tree Column
This is my last newsletter and tree column. My family is being transferred to Italy for three years. If there’s anything to report about trees and wildlife in Rome, I’ll send a dispatch, but the wildlife will probably be of a different nature.

Before turning to trees, I’d like to say what a rewarding experience it has been editing this newsletter. Thanks to Bruce for providing me the design and training to get started. Thanks to my ad man, Marty. Thanks to my newsletter carriers for going out in all kinds of weather to bring the newsletter to your home. Thanks also to my skillful writers, without whom there would be no news. And of course thanks to my husband for doing even more work on the newsletter than I do, even though I get all the credit and the glory. Oh the glory.

Over the last two and a half years, I have gently nudged my neighbors in the direction of tree planting, tree care and native gardening for invertebrate and vertebrate biodiversity support. I’d like to recap here the concepts I think are most important and urgent.

Plant native trees for all their benefits. Trees save energy and save you money. They purify the air and the water. They conserve the soil and provide wildlife food and shelter.

Not all native trees are equal. We’re lucky in the mid-Atlantic region because Dr. Doug Tallamy at the University of Delaware has been measuring which trees provide the most benefit to wildlife here. His prioritized lists can be found on his website. But basically, the most valuable natives for wildlife support are oak, cherry, willow, birch, poplar, crabapple, blueberry bush and maple. Be sure to plant local, native versions of these plants because European and Asian plants don’t feed the invertebrates that are the foundation of our local food web. Read Dr. Tallamy’s book Bringing Nature Home or simply click on “What to Plant” on his website http://bringingnaturehome.net/

Water young trees 25 gallons a week. Every weekend, take stock of the previous week’s rain. If it hasn’t rained much, soak the ground around the root spread, which is at least as wide as the canopy spread.

Plant trees in the right spot. Determine the height and canopy spread the tree will have at maturity. Make sure it won’t inter-fere with power lines, buildings, driveways and neighbors’ property. Call Miss Utility before you dig. In Virginia, dial 811. http://va811.com/

Put mulch under trees instead of grass. Spread it 3 inches thick and keep it 3 inches away from the trunk. Spread it out as wide as the farthest branches. Each year, make the circle a bit wider. Mulch keeps roots moist, provides nutrients and keeps down weeds. It also keeps lawn mowers and weed whackers away from the trunk. Arlington leaf mulch is awesome. Pick some up for free or have it delivered for a small fee: http://www.arlingtonva.us/departments/EnvironmentalServices/SW/Residential/page83856.aspx

Leave the leaves. Trees make their own best mulch by dropping their leaves. Even evergreens drop their leaves, just not all at once. Rake the lawn, driveway and patio, but leave a circle of leaves at the base of each tree, and leave the leaves that fall on your flowerbeds as well. Not only do they benefit from the nutrients and moisture, but the leaves contain the larvae and pupae of next year’s butterflies!

Let me tell you ’bout the birds and the bees. Native plants support moths and butterflies, who in turn support the birds. They also provide food for pollinators. Simply put, native plants are the foundation of the web of life. Don’t forget we are caught up in that web.

Tolerate some leaf damage. Native plants help insects by being their food. If there are holes in your foliage, it means you were successful in choosing good bug food.

And last, but certainly not least, take ivy off trees. What looks like a lovely little green plant can actually strangle trees, accelerate rot, attract mosquitoes and cause mature trees to fall down during storms. Visit the TreeSteward website for more information on ivy removal and tree care, and visit the master gardener and tree tables at the Arlington Courthouse Farmers’ Market on Saturdays in summer.

Cory's Baked Native Garden

Today was the hottest June day in Washington, DC in recorded history, at 104 degrees F.  It's been over 100 degrees F. for a couple of days now here in Northern Virginia, and I'm watching as my native garden bakes. Leaves are drooping, flowers are turning brown, and not even early morning watering perks them up. I'm watching four years of planning, purchasing, planting and nurturing native plants as they wilt, and I'm wondering if they will be hardy enough to withstand this assault. I'm hoping that, as natives accustomed to this climate, they have programmed in their genetic code a mechanism to protect themselves from this dry heat.  And if the leaves and flowers don't hang on, will there be time this season for the plants to grow new leaves and flowers?

I tout the benefits of growing native plants to my neighbors, and one of the selling points I use is that the plants don't need as much care, don't need as much water, don't need fertilizer, because they have adapted to our soil and climate over thousands of years. I guess what we're going to see is how well they handle an extended period of dry heat.

We just got hit with a frightening and severe thunderstorm tonight, a rare weather event called a Derecho, which is sort of a long, horizontal tornado, fueled by dry heat on the front side and cooler rain on the back side. The derecho caused a huge, multi-state swath of downed trees, deaths and power outages. Hundreds of thousands of households, businesses and government agencies lost power for days. We were very lucky in our home to have no damage, but there were trees snapped off like toothpicks, with at least 5 trees blocking streets within 5 blocks of our house.  We hosted one family seeking refuge from their unbearably hot house, and others stopped by to charge phones and cook food to use it up before it went bad.  Actually, I observed a great deal of  camaraderie and cooperation among neighbors over the last few days.  The storm brought the temperature down about 20 degrees in 20 minutes, but the temperatures are going to stay in the mid- to high 90s for the next nine days. Poor plants. Poor bugs. Poor birds. Poor mammals.  We shall see how this all turns out.