Water Conserving Benefits of Trees

1. Waterwise Gardening
Los Alamos Cooperative Extension Service and the Department of Public Utilities
Photo: Robert Villegas, CanyonEcho Graphics, Los Alamos, NM 2006
MAY 2007 Water Conserving Benefits of Trees
WG05-07-JWH This month’s newsletter is dedicated to on plant materials are crucial to long
trees. An essential element to the waterwise term success and prudent use of water
This Issue garden, trees offer aesthetic and practical resources in the garden. Some important
benefits alike. Visually they anchor the plant characteristics are size, hardiness,
Water Conserving
landscape design and provide vertical susceptibility to insects and diseases, and
Benefits of Trees
contrast to smaller plants. For water soil and water requirements. The following
Tree Considerations conserving purposes, they reduce heat is offered to assist in making proper choices
• Determining Land- and evaporation by shading the soil and when considering the addition of trees to
scape Needs blocking the wind. Moreover, they provide the landscape.
• Selecting the Site shade to cool homes, reducing energy and
• Needs of the Tree evaporative cooler water use. Carlos Valdez, Horticulture Agent
• Water Needs Cooperative Extension Service
However, before going to the garden center (505) 662-2656
Plant of the Month
or nursery, homeowners should do their http://www.l o s a l a m o s e x t e n s i o n .n m s u .e d u
Drought Outlook homework. Like turf, trees are major water
users in the landscape. Proper consideration Department of Public Utilities,
May/June of landscape needs, examining planting (505) 662-8130
Events sites, and obtaining pertinent information http://www.losalamosnm.us
David Salman
Discusses
Tree Considerations
Determining Landscape Needs Size - Consider the growth habit of the tree.
Rock Gardening Because there are so many different types of Evaluate the size of the tree when mature
(Growing in Tuff ) trees from which to choose, you can select and where it is to be used. Tall-growing
Salman with Santa Fe varieties specifically suited to your needs. trees, such as the Blue Spruce (Picea
Green House will discuss First identify exactly what function you pungens) and Chinkapin Oak (Quercus
how to successfully grow want your tree to serve. Trees may be used muehlenbergii) are suitable for two-story
plants in tuff or volcanic for shade, ornament, screens, reduction of and larger buildings. However, they tend
ash deposits wind and noise, and to shelter wildlife or to dominate the low flat appearance of -
Thur., May 17th, provide edible fruit and nuts. The intended - or even hide -- one-story buildings. For
7 PM at Fuller Lodge purpose will influence your selection criteria attractive and proper balance with one-story
2132 Central of planting site, shape, size, type of foliage, buildings, trees that do not grow over 35
Los Alamos, NM and other physical characteristics. feet are better scaled and require less water.
(505) 662-2656 Trees can rarely be kept small by pruning,
Bernd Leinauer’s Shade - Providing shade usually requires and to do so requires intensive maintenance
Efficient Turf tall, sturdy, long-living species. Density of and makes trees more susceptible to insects
Workshop foliage and shape determines the amount and disease. For trees that are 35 feet or
Attend this one day of shading a tree will provide. Be aware smaller, consider planting the Lacebark
hands-on workshop about that some trees produce a very dense shade Elm (Ulmus parvifolia) or Bigtooth
strategies to efficiently that will prevent grass from growing since Maple (Acer grandidentatum). Careful
irrigate turfgrass with grass requires abundant light. Trees such consideration of mature sizes will reduce the
turf specialist as Green Ash (Fraxinus pennsylvanica) or need for pruning.
Bernd Leinauer Little Leaf Linden (Tilia cordata) provide
Fri., June 15th, ample shade, while trees like Thornless Selecting the Site
9AM - 12 PM at the Honeylocust (Gledetsia triacanthos inermis) When planting trees consider not only what
Los Alamos Golf Course cast a much lighter shade and is more time of year you will be using the space, but
(505) 662-2656 compatible with turf. what time of day as well.

2. Summer Shade - Determine from sketches and observation great deal of water. Fruits and seeds that are large, messy, smelly,
where the tree should be for maximum summer shade. Then or otherwise obnoxious should not be selected for use in lawns or
check the shade movement of this spot. near patios and decks. Also consider abundant
Use a long stake or board and fix it at the Noon
3 pm N shedding of twigs and small branches, allergenic
selected point. Watch the shadows to 9 am or poisonous parts, thorns, weediness, longevity,
Los Alamos Cooperative Extension Service and the Department of Public Utilities
determine if they coincide with your plans. July etc. Finally, strive for diversity. A diverse urban
Shade patterns of a 20-foot tree during summer. forest will lessen the impacts of disease and insect
Location to Maximize Water - If epidemics such as the recent pine bark beetle
possible, plant new trees in valleys and/or Noon
outbreak.
3 pm
depressions in the landscape so rainwater 9 am
will naturally collect and give the tree a Water Needs
good soaking. 0 5 10 15 20 25 September Newly Planted Trees- Irrigate newly planted
Feet
trees at the base, making sure to wet the entire
Avoid Sites Near Utilities -Determine location of overhead and root ball area. Water as needed, perhaps as often as twice a week
underground utility lines. Remember, trees are more than just during the first growing season. Young trees (up to two years
what you see overhead. Often, the root area becomes larger than after planting) should continue to be watered at the base, but the
Waterwise Gardening
the branch spread above ground. Please call New Mexico One diameter of the zone of wetted soil should expand outward as the
Call at 1-800-321-ALERT (2537) before you begin to dig. The tree grows. Check the soil periodically to see if it is dry; allow the
location of these facilities should directly correlate to your choices soil to dry moderately between waterings.
of tree type and site selection.
Watering Established Trees- Established trees should not be
Needs of the Tree watered at the trunk. Instead irrigate from the drip line (the edge
Once you have determined placement of the tree, you must of the tree’s leaves) outward. The distance will depend upon the
evaluate what you have to offer it. Additional site characteristics size of the tree and the nature of the tree’s root system. As a basic
that should be reviewed include the space available, the rule of thumb, apply water in a circular band that’s at least half as
environment, soil conditions, and potential pests. Consider both wide as the distance from the trunk to the drip line.
the size and the shape of the available space and how that will
change as the tree matures. Trees prefer to be watered slowly and deeply. Watering trees
deeply, but less often will keep roots from surfacing and make
Environmental characteristics include extreme heat or cold, them less susceptible to mechanical damage from lawn mowers
drought, exposure to wind and street-side pollution. Soil pH, and weed-whackers. Use a bubbler, multiple drip emitters, or a
drainage, and depth are all factors to consider when selecting hand-held hose to deliver water to the tree’s root zone. Moisten
trees. Most trees will require a minimum of 18-24” of well the soil about 18 inches deep each time you water, and let the
drained soil. Soils with high salinity, low fertility, or toxic surface dry between waterings. Water established trees once
pollutants will limit tree selection. Potential pests include insects, every two weeks during the growing season, and once a month
diseases, mammals like deer and rabbits. The likelihood of future during the dormant season.
wildfires should also be a consideration. Coniferous evergreens
Plant of the Month
burn hotter and longer. Use the information about your site to
select a species or variety that is well suited to the challenges to
which it will be subjected.
Western Bigtooth Maple Tree (Acer grandidentatum)
Consider how much maintenance the plant will require and any Vermonters may boast, but for landscape color as dazzling as
possible disadvantages. Fast growing trees such as poplars and a sunset just look in our own backyard - the Bigtooth Maple
willows, although providing quick shade, are short-lived, have of the mountain west is imposing in all seasons but its autumn
brittle wood that is easily damaged by wind and ice and use a coloration is spectacular. The color variation is genetically
determined. In early September
the maples begin to change ©Texas Agricultural Experiment Station.
U.S. Drought Monitor colors. The color variation from
one tree to the next is quite
http://aggie-horticulture.tamu.edu/
http://www.drought.unl.edu/dm/DM_west.htm striking. They’re not really
Intensity:
D0 Abnormally Dry bushes, but neither would one
D1 Drought - Moderate
D2 Drought - Severe NV consider them trees according
UT
D3 Drought - Extreme CO to the standard of the Eastern
D4 Drought - Exceptional CA
hardwood forests. These natives
AZ of the intermountain states grow
NM
Released April 19, 2007 to heights ranging from 20 to 25
Author: David Miskus, JAWF/CPC/NOAA
feet with trunks 9 inches in diameter. The height variation
depends on soil conditions and available moisture. So what if a
The Drought Monitor focuses on broad-scale conditions. Local conditions may
Vermonter would scoff at our maples -- things are different west
vary. Visit http://drought.unl.edu/dm for additional text summary for forecast
statements. of the Mississippi.
OF LOS A
TY
New Mexico State University is an equal opportunity, affirmative action employer and educator.
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NMSU, the U.S. Department of Agriculture and Los Alamos County cooperating.
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