Friday, February 21, 2014

How to Get Trees to Survive Drought

It is rare for mature trees to die except in the most extreme of circumstances (from disease or drought).  Yet young, newly planted trees frequently don't make it through their first year.  There are several reasons that newly planted trees are so likely to die.

First, many store bought trees are dug up prior to sale, and much of their root mass is removed during this transplant process.  This can be so traumatic that the tree can have trouble pulling enough water and nutrients from the soil to sustain its trunk, branches, and leaves.  This then results in leaf loss, which means less energy available to grow deeper or wider roots.  If a tree does survive this downward spiral, it may be weak for years to come, and frequently doesn't exhibit strong growth for several years after planting.

More frequently, trees are acquired from a big box store in pots that they have been growing in for several years.  This presents an entirely different problem.  People usually select the tree based on a healthy appearing canopy, and only at planting do they realize how container bound and misshapen the roots have become.  This tree can be planted, but these disfigured roots will cause many problems for the tree.  First, the tree will be more likely to shift or blow over in high winds.  Secondly, as the tree now lacks its primary root, the roots will grow laterally and stay near the surface.  This means they can quickly absorb moisture when it rains, but are very prone to drought damage when there is no rain and the upper level of the soil dries out.

The only real way to combat these two problems with the roots of store bought trees is frequent watering.  Depending on the number and size of the trees, this usually involves bringing a hose or large watering can out to the trees at least twice weekly.  The hose must then be returned.  Most of the water given to the tree is of course wasted (as it evaporates or bypasses the roots upon entering the soil).  This approach is very time intensive, and can be very expensive depending upon water cost in the summer.

A smarter, more efficient, less expensive, less time consuming, and more natural way to plant trees is planting with the Groasis Waterboxx.  When planting with the Waterboxx, you purchase (or find) smaller trees referred to as saplings, which still have healthy, intact primary roots.  These trees can be purchased for much less (usually around 1/10 to 1/25th the cost of store bought trees) from arborday.org and other sites.  One to two of these trees are then planted with each Waterboxx in small holes.  The Waterboxx is filled with water one time only.  This water, as well as new water collected from dew and rain, is slowly released through a wick in the base of Waterboxx to the roots of the young tree.  This induces the tree's primary root to grow straight down (vertical) rather than out (lateral) like you would get with frequent hose watering.
Originally from Groasis.com


The Waterboxx planting method is so effective that when two trees were planted in each Waterboxx, 99% had one surviving after one year in a Sahara Desert planting trial  After the tree's root reach deeper underground water (usually around a year after planting), the tree experiences a growth spurt and becomes too large for the Waterboxx to remain in place.  At this time, the Waterboxx is carefully removed (being careful not to damage the tree's canopy), and reused for up to ten years.  The Waterboxx planted tree is then resistant to drought due to its deep roots away from the drier top layer of the soil.  The Waterboxx method also means much faster growth for the tree, as there is generally no period of die back and transplant shock from which to recover.  The Waterboxx never needs to be refilled, and only needs to be revisited when it is removed.
Originally from Groasis.com

The Groasis Waterboxx has an up front cost separate from the cost of the tree, while store bought trees only have one (albeit usually high) price.  For this reason, tree planters sometimes lean towards larger store bought trees without using the Waterboxx.  However, when all factors are considered (including the cost of labor and water, cost of potting soil, and other costs), the Waterboxx almost always pays for itself in the first year of use.  You can enter numbers yourself on our Waterboxx cost calculator, and see if the Waterboxx makes financial sense for you.

Regardless of the financial case for buying a Waterboxx, the Groasis Waterboxx will dramatically increase tree survival, conserve water, and decrease work of planting new trees.  You can buy the Waterboxx from Dew Harvest in the United States. We would love to hear your comments below - to leave one, please click on "Comments".

Our Sources:
http://www.clemson.edu/extfor/urban_tree_care/forlf17.htm

Tuesday, February 18, 2014

Root Growth with the Groasis Waterboxx



  Roots are not something many people consider when thinking about plants and their health, but they truly are very important.  Like an iceberg with much of its mass hidden beneath the surface of the ocean, the roots of a plant or tree, although invisible, can determine whether that plant is able to make it through a drought or strong wind.  Deep roots are necessary for these two main reasons.  

 Skyscrapers must have excellent foundations, which extend well beneath ground level to prevent toppling over in high winds.  Similarly, for trees to remain upright in gales they need a well developed root system.  When large trees are bought from nurseries they are almost always in small pots, because consumers generally want a large canopy and forget about the hidden root system.  You frequently bring the tree home to find that the roots have been circling at the outside of the pot for years.  These roots are a mangled mess, and the tree will have difficulty reorienting them downward as many are now facing sideways.  This means that, once the tree is planted, the roots will stay near the soil.  This is bad for two reasons: First, a shallow root system makes the tree prone to collapse in wind. Of more consequence recently, however, shallow roots virtually guarantee that the tree will not make it through periods of drought, when the top layers of the soil have all of their water evaporate.  

A tree with deeper roots, penetrating down farther into the soil, can tap the moisture at those deeper levels and bring it to the growing tree.  It is for this reason that well developed trees can grow in the desert, but new trees are hardly ever established there.

The Groasis Waterboxx was designed with root structure in mind.  It is designed to be used on smaller trees (less than 2 inches in diameter, of the type grown from seed or available from www.arborday.org) that don't already have deformed root systems.  The Waterboxx slowly releases stored water, about 50 mL (10 teaspoons) a day, directly beneath the tree in a vertical water column.  This vertical water column induces the tree to grow its primary root straight down, providing stability and eventually reaching ground water.
Originally from Groasis.com


Once the root reaches ground water, it will experience a burst of growth from greater water availability and the Waterboxx can be removed and reused up to 10 more times.   Even in very dry areas, there is usually enough rain for the trees to grow if good root systems are developed.  If you are interested, you can buy the Groasis Waterboxx here or learn more about the Groasis Waterboxx hereWe would love to hear your comments below - to leave one, please click on "Comments". 






Saturday, February 8, 2014

Water's Near Miraculous High Specific Heat Capacity

Which is easier to warm up 100 degrees on the stove: a one pound copper pot or one pound of water in that pot?  It is an interesting question, and one with profound implications for life on Earth.  The answer - copper is much easier to warm than water, because water has a very high specific heat capacity.

Specific heat capacity is a mouthful, but it is just a way of saying that for a given amount of a substance (like water), it takes a certain amount of energy to increase temperature.  Metals like copper have a very low specific heat capacity (copper's is 0.385 J/g to raise the temperature 1°C).   In other words, metals are very easy to heat.  


Water, however, has a very high specific heat capacity (4.184 J/g to raise temperature 1°C).  It resists temperature changes even with large amounts of energy.  This is why on sunny summer day at the beach, the temperature of the air can be quite hot while that water can remain chilly.  This is also why lakes remain warmer than the surrounding air well into the winter.  Because of this delay in the cooling of the Great Lakes, for example, cities from Chicago to Cleveland to Buffalo get a great deal of snow, as precipitation evaporates from the lakes in the beginning of the winter and is then deposited as snow.  



This graphic shows the hydrologic cycle and how the coastal areas have more temperate (and wetter) climates due to the high specific heat of water - From USGS
This high specific heat capacity of water has profound effects (along with ice's decreased density relative to liquid water) on life on earth.  Because water doesn't quickly change temperature, fish don't have to worry about being boiled during a hot day in a river in the desert, and then frozen at night.  

This high specific heat capacity of water is also why areas near coastline have less extremes in their temperatures than areas farther inland.  Water resists changes in temperature, and imparts this resistance to nearby land through slow release of heat and evaporation.


Why is this relevant to planting trees with the Groasis Waterboxx?  The Waterboxx has a large basin which holds around four gallons of water.  This basin surrounds the trunk of the young tree, and prevents the tree from undergoing large swings in temperature between the day and the night.  This can prevent freezing on cold nights, and heat damage during hot days.  This allows trees to spend more time in a temperature range where they can grow.  The Waterboxx basin essentially forms a little coastline right next to the tree, preventing rapid swings in temperature.  


In winter, even though the water inside the Waterboxx may freeze, the Waterboxx's up-sloping design prevents it from cracking.  Once the temperature again reaches above freezing, the Waterboxx begins releasing water to the plant's growing roots.  


The Waterboxx has many more design features garnered from a better understanding of nature (search this blog for some).  It allows you to grow trees where no one thought possible, with no electricity and no irrigation.  It helped 88% of trees (99% when using two trees) survive in a Sahara Desert planting trial, vs. 11% for traditional planting. In the United States, the Waterboxx can be purchased from Dew Harvest.  
We would love to hear your comments below - to leave one, please click on "Comments".


Our sources:


http://ga.water.usgs.gov/edu/heat-capacity.html


http://floridakeys.noaa.gov/ocean/weather.html


Friday, February 7, 2014

Riparian Buffers - Reforesting Waterways

Today we are going to write about Riparian Buffers - or planting trees and other plants along waterways.  This may seem like an odd topic given the blog's title of "The Arid Arborist."  However, we feel that the uses of trees should be enumerated at every opportunity, and proper care of our waterways encourages tree growth everywhere.  We will both discuss the uses and challenges of planting along waterways, and ways in which the Groasis Waterboxx may help.

First, what is Riparian Buffer?  A Riparian Buffer is a green zone planted with native trees, shrubs and grasses along a waterway that protect against non-point source (generalized) pollution, inhibit erosion, and provide habitat for wildlife.  These may also serve the very important goal of windbreak and flood mitigation.  Riparian is derived from "ripa" meaning bank in Latin, from which our word "river" is clearly derived.
Riparian Buffer in Iowa - From Wikipedia

Uses of Riparian Buffers

Sediment Removal - In one paper (Mankin, 2007), the authors found that Riparian Buffers stopped over 97% of sediment from entering the waterway.  This same study found over 90% of fertilizer components (which can cause choking algae blooms near the mouth of rivers) were stopped by Riparian Buffers.  The effects of erosion into our waterways can perhaps best be seen at the Mississippi Delta, were millions of tons of topsoil is lost to the Gulf of Mexico.

Windbreaks - While the research on Riparian Buffers as windbreaks is not as robust, the use of trees elsewhere as windbreaks is well known.  If planting for windbreaks in temperate regions (all of the United States), conifers should be used extensively as these will work in winter when deciduous trees have lost their leaves.

Flood Mitigation - Riparian Buffers allow heavy rains to more slowly reach waterways through several mechanisms.  First, plants form physical obstacles to water as it flows downhill (imagine a ball rolling down a flat piece of plywood versus a pegboard with pegs every 2 inches).  Second, the roots of the plants loosen the soil and allow water to percolate downward to underground aquifers rather than all staying on the surface.  Finally, plants transpire (absorb and then emit as water vapor) huge amounts of water, turning liquid water into water vapor.  If the Riparian Buffer is used for flood mitigation, grasses, shrubs and trees are useful.

Litter containment - it is deeply distressing to the author how much preventable litter we see floating into our nearby creeks.  Much of this is unintentional - trash left out for pick up and then blown into a creek by strong winds (another reason for windbreaks), but Riparian Buffers would enable the trash to be stopped before entering the water and becoming a danger to fish and other wildlife.  The trash is much easier to remove near the base of trees rather than from the bottom of a swollen stream, or worse, the center of the Pacific Ocean.

How Can the Groasis Waterboxx Help?

What role can the Groasis Waterboxx play in Riparian Buffers?  We have tried multiple times before the Waterboxx to plant different trees along stream banks.  Our first effort we planted 2  8 foot tall Weeping Willows (Salix babylonica) approximately 5 feet above the level of a nearby creek.  We believed that rainfall would be sufficient to get the willows' roots to the moisture at the water level.  In this we were mistaken.  The summer following planting was very dry, and even weekly watering didn't save our willows.  Next we tried planting both one smaller weeping willow and several bald cypress (Taxodium distichum) right along the water level (during a relatively wet period in spring) realizing that our trees may be washed away in heavy rains.  Our trees were not washed away, but the bald cypress never bloomed due to unknown reasons (possibly because it was in a frost pocket which injured it).  This weeping willow did do quite well for a time, doubling the size of its canopy in less than a year.  However, during a dry summer spell, the water level of the creek fell well below the roots of the willow, revealing that the willow roots were barely in soil and mostly in the creek itself (now in open air).  The willow quickly died.  The Groasis Waterboxx solves both the problem of inappropriate amounts of water and frost pockets.  If we had planted our trees at the top of the creek bank with the Groasis Waterboxx, we would have provided the trees with just the right amount of water to sustain them during dry spells without opening them to flooding that would expose and then kill their roots.  The trees also would have been better positioned to serve their proper purpose in the Riparian Buffer, slowing flood waters and preventing sediment runoff.  You can see a video of how the Waterboxx functions below:



The Groasis Waterboxx dramatically increases tree survival (up to 99% when done properly in one Sahara desert planting trial), and is reusable for up to ten years.  The Waterboxx can be purchased from Dew Harvest in the United States.

More information on Riparian Buffers is available here from the Arbor Day Foundation. We would love to hear your comments below - to leave one, please click on "Comments".