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

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 here. We would love to hear your comments below - to leave one, please click on "Comments". 

Dew Point and Condensation - Planting Trees with the Groasis Waterboxx

     Dew Point is an interesting and often misunderstood concept.  Dew Point is the temperature that air must reach (decrease to) in order for condensation to take place - the Point on the thermometer at which Dew forms.  We frequently see this with glasses of ice water.  Imagine two identical glasses - one full of room temperature water and one full of a mixture of ice and water.  Which one will develop condensation (popularly known as 'sweat' although this is a very misleading term)?  Experience has probably taught you that only the glass of ice water will induce condensation, sometimes in significant amounts.  The author has even had a cellphone ruined when it was placed next to a glass of ice water in a humid room overnight.  The condensation produced by the glass created a puddle that destroyed the cellphone without the water ever being spilled. Why does this condensation happen?
     Air can hold water in the form of vapor - and warmer air can hold more water vapor.  When you fill a glass (and a glass works better than a plastic cup as glass is a poor insulator) with ice, it cools the air immediately around it.  This local air is cooled below the Dew Point, and the water vapor from the air condenses.
    This is actually why mountains cause rain - as humid air from plains or oceans has to rise to cross over mountain ranges, it cools.  Depending on the height of the mountain range, it usually cools enough for some of the air to lose water in the form of precipitation (rain or snow).
     Why is any of this relevant to anything?  Well, much of the fresh water available on the Earth is actually in the air.  In fact, over 5 times as much water is available in the humidity in the air as is available in rivers on the Earth.  
     As so little water is available in some areas where trees and other plants need water, a brilliant Dutchman name Pieter Hoff invented a device to use water from the air to grow plants without irrigation.  This device is called the Groasis Waterboxx PlantCocoon®.
    The Groasis Waterboxx acts acts in several ways.  The Waterboxx has a reservoir of several gallons of water that is resistant to swings in temperature due to the high specific heat capacity of water.  There is a small air pocket above the water reservoir and immediately below the Waterboxx lid.  The water tends to be cooler than outside air during the day and warmer than the outside air at night.  When the sun sets and the outside air temperature cools, the air pocket between the water reservoir and the Waterboxx lid is cooler than the outside lid (just like a glass of ice water is cooler than the ambient temperature) causing condensation to form faster and in greater amounts.

Originally from Groasis.com

    The Groasis Waterboxx lid is specially designed with microscopic pyramids on top of a funneled, corrugated form.  This design mimics the lotus leaf, and funnels as much dew as possible to the central siphons.  These siphons direct the water collected as dew into the reservoir, and prevent the water from evaporating during the day.  This water is then slowly released to the roots of the growing plant below by a small wick at the base of the green reservoir.  This whole process can be seen in the video below.

 
     The Groasis Waterboxx will collect dew every night, so long as the temperature of the air both rises above and below Dew Point (allowing condensation to form).  It will take up to a year without any rain to empty the reservoir if it is refilled with condensation.  Dry, arid climates that are most in need of the Waterboxx generally have the biggest swings in temperature between day and night due to lack of insulating cloud cover.  These swings mean the temperature is more likely to go both above and below Dew Point, causing condensation.  The Waterboxx works so well in the desert that when used in the Sahara, 88% of single trees (99% of double tree plantings) planted with the Waterboxx survived even though they were never watered again after first planting.  Only 11% of the weekly watered control trees survived.    You can check Dew Point here if you have relative humidity and temperature handy (available here).

What about areas that are so hot and so dry that dew is rarely found on the ground in the morning - can the Waterboxx work there?  Yes, and here's how:

Trees transpire a considerable amount of moisture, and a Waterboxx planted tree of any size (but especially broadleaf/deciduous) would transpire water vapor over the Waterboxx lid.  On a windless or nearly windless night, this would settle on the lid, slide down into the siphons and replenish the reservoir.  This would be the case even if the relative humidity elsewhere around the tree was so low that the low temperature wouldn't reach dew point.  If a tree is established as recommended with the Waterboxx (with 10 gallons of water poured at time of planting into the soil), that is somewhere near 10 gallons that can be transpired, collected, and recycled.  This 10 gallons doesn't include the amount in the reservoir at planting and the amount collected from dew and rain.  

 Also, the Waterboxx planted tree may lower the daytime and therefore nighttime local temperature slightly (due to shade and humidity), and the local air may reach dew point that way.  Finally, in the beginning of the summer, the water in the reservoir is likely to be cooler than the average air temperature.  This will likely cool the small amount of air in the Waterboxx (the air resides beneath the cream colored lid but above the black midplate), making the surface of the cream colored lid cooler and closer to dew point. So, because the Waterboxx planted tree changes the locally environmental conditions, the Waterboxx can be replenished even if the surrounding environment is too hot or dry.

A Waterboxx lid with significant condensation.  This water beads up due to the microscopic pyramids on the Waterboxx lid.

A note about published Dew Points.  We find these to be quite frequently inaccurate.  We have been camping and have had our tent (and the surrounding ground) covered with dew when by published temperature and dew points, there wasn't any condensation.  Dew points can be highly local (due to differing local water sources) and the only real way to measure it is to record the temperature outside when dew begins to form on the ground (or other objects).  

If this all sounds a bit complicated, well, unfortunately that's because it is.  That is likely why a device like the Waterboxx, deceptively simple as it appears, was never developed before.  We will continue to update this site with our results, but the best way to understand the Waterboxx is to buy one yourself.  As always, you can buy one, five, or ten, twenty or fifty Waterboxxes from our parent website, Dew Harvest. We would love to hear your comments below - to leave one, please click on "Comments". 

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

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 being used 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.

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.

The Groasis Waterboxx from Dew Harvest

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".

Sources: Mankin, K. (2007). Grass-shrub riparian buffer removal of sediment, phosphorus, and nitrogen from simulated runoff. JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, 43(5), 1108-1116. 

Evergreen Hedges - Tree Selection and Maintenance

     As Americans have rediscovered their back yards over the past several years and decided to spend more time in their current home because of the recent recession, more have decided to plant evergreen hedges.  The advantage of hedges are obvious - privacy, sound reduction from nearby streets and neighbors, habitat for wildlife, as a windbreak lowering heating costs in winter, and improvement in home value and curb appeal.  Unfortunately, we have seen a significant number of dead hedges over the past several years - mostly due to inappropriate trees for the area, inappropriately planted and insufficiently watered during the recent droughts.  We will attempt here to educate on the best types of evergreen tree for certain growing conditions, and how the Groasis Waterboxx might be useful in the planting of the hedge.  For the purposes of this post, we will only be discussing trees that grow at least to eye height (thereby blocking line of sight).

Arborvitae

      In the Great Lakes region where we are based, this is definitely the most popular hedge tree.  The Thuja occidentalis 'Emerald' variety seems to be the most commonly planted, but sometimes the faster growing if less picturesque Thuja standishii x plicata 'Green Giant' is used.  Both of these arborvitae (Latin for "tree of life") can be grown in zones 5-7, with the 'Emerald' variety hardy to zone 3 (see zones below).  

USDA Hardiness Zone Map - From Wikipedia

The 'Emerald' variety has a very nearly cylindrical appearance (with a slightly tapered spire), but tends to grow only about 12-18 inches per year, and reaches it maximum height of 20 feet slowly.  The 'Green Giant' variety can grow up to three feet a year under ideal conditions, and can potentially grow to 60 feet in height.  Both of the arborvitae are extremely sensitive to drought.  Over the last three summers, we have seen approximately 60% of established arborvitae die and 90% of newly planted arborvitae perish.  These trees, when bought potted from nurseries, almost always have a thick root ball when their base is removed from the pot.  Even when properly planted, these roots tend to stay near ground level, and will quickly dry out in periods of even partial drought.  One solution to deal with this is the rather arduous task of snaking a soaker hose throughout the trees every spring, and watering them thoroughly at least once weekly.  The soaker hose will need to be removed and stored before freezing in winter.  This can quickly become expensive, and tends to further cause roots to grow near the surface.  A (far cheaper) solution is to plant small bare root arborvitae (available from Arbor Day for as little as $2.49) using the Groasis Waterboxx.  The Waterboxx allows you to plant smaller, much cheaper (potted arborvitae sell for around $35 at big box home improvement stores due to the recent die off) arborvitae with properly formed roots.  The Waterboxx induces the roots of the tree to reach downward toward capillary water, not laterally (staying near the surface).  Because the Waterboxx contains a water reservoir and collects dew, you will not need to irrigate the trees after planting.  After approximately one year (depending on growth), the Waterboxx can be removed and reused.  You can calculate whether using a Waterboxx will save money during the first year using our calculator.  

Leyland Cypress

The Leyland Cypress (X Cupressocyparis leylandii) is also an excellent evergreen hedge tree, with the ability to grow much farther south than the arborvitae (up to zone 10).  The Leyland Cypress is also considerably more drought tolerant, as well as faster growing than the 'Emerald'  arborvitae.  The drawback to this tree is its mature size (up to 60 feet) and its susceptibility to infection.  As with the arborvitae, we recommend planting bare root Leyland Cypress using the Waterboxx, giving the tree an excellent foundation with deep roots.  The Waterboxx can be removed and used again to extend the hedge or to plant other trees.  

It is important to be a good (and thoughtful) neighbor when planting hedges, not planting tall plants that will block sun from reaching a neighbor's yard.  Also, each of the hedge trees discussed here can get certain diseases (arborvitae are susceptible to bagworms [Thyridopteryx ephemeraeformis] which appear to be pine cones at first sight) that will need to be dealt with immediately if spotted.  These diseases are more likely to take hold of unhealthy trees, another incentive to use the Waterboxx to properly establish the hedge at planting.

Be the first in your area to start growing plants with the Groasis Waterboxx. The Waterboxx can be purchased in the United States from Dew Harvest, with discount prices on orders of five or ten. We would love to hear your comments below - to leave one, please click on "Comments".