Proper summer watering of trees

Summer has an intriguing way of luring in longer days, sunnier skies, and vibrant landscapes. For many, summer is a calming retreat after enduring what felt like an endless winter. Naturally, with heat waves we feel inclined to water our trees regularly, but it’s easy to get carried away and over-water. While we have suffered through drought conditions here in the Heartland, other areas have had to deal with heavy rainfall, even flooding. The following are a few rules of thumb to keep in mind when watering your trees.

With differing climates and varying landscapes, it’s hard to quantify how much water trees need because irrigation will vary from one species to the next. Young trees and those transplanted will call for more water because they’re burning lots of energy establishing their roots in the soil.

Hose_deepwater[1]For young trees we encourage a deep-watering by running the hose over the root zone for about 30 seconds. The idea is to reach the full root depth and keep the soil damp, not soggy. Mature trees are best left to nature; unless you’re suffering from severe drought conditions, let your rainfall do the watering. Be cautious not to overwater, as it can drown the tree roots. If a puddle remains after watering then take it as a sign of too much watering. Other signs to look for include yellow leaves, usually starting on the lower branches, wilting, brittle green leaves, or fungus growing on soil surface. If your soil is wet and you notice any of these changes, you may be overwatering your trees.

Ooze-TubeGallons_1-885[1]A soil probe is helpful in learning how dry or saturated your soil is and can set the tone for watering frequency.You can also test soil moisture by hand. If a planting site is properly hydrated you should be able to compress the soil into a ball that will crumble when gently rolled between the palms of your hands. No need to dig deep, one to two and a half inches below ground level is sufficient in testing the moisture content.

Ooze tubes—an automated drip irrigation system— are another great method for controlling water time and ensuring your trees are receiving adequate water.

Mulching is a great practice to implement in tree care, especially if you’re dealing with drought conditions. Mulch retains water, helping to keep roots moist. DSC00575_000[1]Another tip to avoid drying out soil during times of drought is to stay away from commercial potting soils and fertilizers. Salts and other additives in fertilizers such as Miracle-Gro can cause root burn, adding additional stress to trees. Proper tree pruning improves limb stability and structure, and removes dead branches, which decreases tree tension and allows water to move where needed most in the tree.  Also, avoid digging holes in the ground as an effort to water deeply; it will only dry out the roots even more.

With your help, the season of sun can work in favor of your trees. You can read up on other great ways to save water in our How to Landscape to Save Water Tree City USA bulletin. What other tips do you practice in keeping trees appropriately watered during the summer season?

The dish on dirt: why soil is important to tree health

Have you ever planted multiple trees or shrubs at the same time and noticed one variety flourishing while the other has no progress? There are numerous factors that could be affecting your plant health, including soil. It’s not uncommon to overlook soil care while planting if you’re new to the green scene. We become so caught up with tree care above ground that we forget what’s happening below is just as important. Since trees grow from the ground up, it’s essential to understand their relationship with soil and the role soil plays on tree health. Using the wrong type of soil, or neglecting to use healthy soil altogether, can be detrimental and cost you your trees.

What works for your pink dogwood trees won’t necessarily work for your blueberry bushes. You see, each tree calls for a different soil type, the most common being sandy, silt, and clay. landsoils1[1]Soils vary from one location to the next. When high-quality soil isn’t present you can mix soils to change textures and create a soil more suitable for planting. Sandy soil has larger particles and a rough texture. Since the soil base is loose it’s harder to retain moisture, making it harder for plants to access nutrients. Silt is comprised of fine particles and has a smooth, slippery texture. Its tight compaction can serve as an advantage in retaining moisture and nutrients, or a problem if planted with the wrong tree.  Clay is the most tightly packed soil with little air space; as a result it makes it difficult for air and moisture to penetrate the soil.


Signs of Chlorosis are typical of a nutrient deficiency.

Soil performs five essential functions; using the wrong type of soil or unhealthy soil can impede tree health by constricting roots from accessing the water and nutrients necessary. Soil helps regulate water, supports biodiversity, filters pollutants, provides physical support, and cycles nutrients. You can understand why attempting to plant a tree that requires less soil saturation may not thrive if it’s planted in silt or clay soil. Signs of unhealthy soil include leaf discoloration, brittle limbs, and even stunted tree growth.


Exposed roots pose as a threat to tree health.

It’s also important to dig a hole deep enough for tree roots to grow. Planting in shallow soil makes tree roots more susceptible to exposure which can lead to tree stress and even toppling due to wind gusts. If you have bedrock near the surface of your soil that prevents you from digging deep you might consider mixing in top soil to add depth.

Plant growth is directly influenced by soil conditions. That’s not to say that if your plants show these signs that it’s a result of poor soil. Several varying factors go into tree health and soil care is one of them to keep in mind while planting young trees.

What tips do you have in maintaining healthy soil for planting?


USDA Soil Health

University of Florida IFAS Extension





NBA Community Forestry Matchup: Miami Heat V. San Antonio Spurs

The National Basketball Association’s finals are set to begin tonight. With two respected teams battling for the championship, we examine each city’s urban forestry program in a challenge of our own. Who will win the championship in our Urban Forestry Matchup?


bayfront1[1]This diverse city of culture, entertainment, and commerce has a lot to offer to travel enthusiasts and international investors; is the city’s tree canopy impressive enough to lure in tree huggers and environmentalist? Let’s see if Miami’s urban and community forestry program lives up to the bill.

Through the Million Trees Miami Campaign, the city aims to improve its current tree coverage standing from 14 percent canopy coverage to 30 percent by the year 2020. The effort engages local organizations, cities, and residents in tree plantings to make Miami a more sustainable city.

The city’s trees remove 2,300 tons of air pollution every year. In addition to the cleaner air the city saves as much as $300,000 in energy savings, not a bad deal for a city with regular sunshine. Miami continues to strive to improve its green standing.

San Antonio

sanantoniotx-downtown-san-antonio[1]Rich in history, sports, and family fun, San Antonio proves to be a city with something for everyone. Does Texas’ second largest city have what it takes to set itself up as a sustainable city? Let’s take a look at San Antonio’s urban and community forest.

Despite impressive tree coverage of 38 percent, in 2011 San Antonio set a goal to increase its tree coverage to 40 percent by the year 2020. With tree initiatives in place and community engagement, the city is continually striving to meet its target.

In fact, the tree canopy removes as much as 13 million pounds of pollution from San Antonio’s air. With cooling costs estimated at as much as $17.7 million annually, the shade provided by city trees confirms the benefits of investing in urban and community forestry.

Community forestry programs are an asset to cities, communities, and neighborhoods, contributing to their environmental and economic well-being. The benefits made possible by a healthy, vibrant community tree canopy are enjoyed by current and future generations.

Which city do you think earns the championship trophy in our community forestry matchup?



American Forests Urban Exosystem Analysis

University of Florida IFAS Extension

Million Trees Miami Campaign

Multiple benefits of urban ecosystems: spatial planning in Miami, USA

NHL Community Forestry Matchup: New York Rangers V. Los Angeles Kings

Anticipation fills the air as hockey fans await the National Hockey League’s final series where the New York Rangers will play the Los Angeles Kings for the Stanley Cup. While ESPN looks at the team stats, we turn our attention to the teams’ city urban forestry stats. Which city will take home the Stanley Cup in our community forestry matchup?

New York City

This city of dreams has a vision of its own: it wants to be America’s first sustainable city. For outsiders, the idea of a greener New York may seem ambitious for such a congested social hub. How will the city achieve such a goal? Simple, through an exceptional and practical effort introduced by former Mayor Bloomberg called PlaNYC. The plan— unveiled in 2007— brought together 25 city agencies to work toward strengthening the economy, combating climate change, and enhancing the quality of life for all New Yorkers. Let’s take a peek at how this plan spans out.

2007-08-18_11-51-18_corrected[1]This city of eight million residents is currently home to five million trees. Don’t be deceived by the concrete jungle, as nearly 40 percent—11,000 acres— of New York City is parkland. The city’s trees remove 2,202 tons of pollution per year. In addition, building energy savings equate to $11.2 million per year. Under MillionTreesNYC, the city aims to plant one million trees by 2017.

Los Angeles

echoparkpic[1]Los Angeles is part of the million tree initiative aimed at planting one million new trees throughout the city. Million Trees LA is a public-private partnership between the City of Los Angeles, local non-profit organizations and businesses. In an effort to reach its goal, Million Trees LA actively provides trees to local residents and businesses.

Los Angeles may be ahead of its time when it comes to Hollywood glamour, but will the city set the trend in environmental sustainability? The city of nearly four million residents is home to 10 million trees. In fact, 11 percent of LA is comprised of trees—15,000 acres. The city’s tree canopy removes 2,000 tons of pollution annually. The city saves as much as $10 million annually in energy savings.

Community forestry programs are an asset to cities, communities, and neighborhoods, contributing to their environmental and economic well-being. The benefits made possible by a healthy, vibrant community tree canopy are enjoyed by the current and future generations.

Which city do you think earns the Stanley Cup in our NHL community forestry matchup?