A cookie walk is not a new dance step–nor is it a bake sale.  But it seemed to be a popular topic in last month’s e-gardens newsletter (related article – Tree Cookies. A unique way to recycle your tree.)  For the sake of brevity, some of the finer details were not included, resulting in a wheelbarrow full of questions.  As you may recall, logs of various sizes can be cut into slices and placed on the ground to form cookie walks or stepping cookies. 

Red Cedar Cookie Walk

Tree Cookies - Bois D Arc Cookie Walk

Red Cedar Stepping Cookies

Here are a few of the finer points about tree cookies.

• Size  The larger the diameter, the more stable the tree cookie.  A 10 to 14-inch wide cookie makes a more stable walking surface than a 4 to 5-inch wide cookie.  Likewise, 3 to 6-inch thick cookie is more stable than a 1 to 2-inch thick cookie.  Soil underneath a cookie, as opposed to mulch, offers more stability in the short term.  In the long term, the mulch offers more stability as it mixes with the soil.  However, the cookies may not stay level.  Thin cookies will crack and split quicker than thick cookies. 
  [photo #4 and possibly #5 of thicker tree cookies]
  

  Thick Cookie Walk

  

  Thicker Cookie Walk – Tree Cookies

• Species  All types of trees can be used for cookies, but avoid using black walnut cookies or black walnut chipped into mulch since they can contain juglone, an organic substance toxic to other plants.
• Longevity  The weaker wooded tree species, such as Willow, Maple, and Cottonwood, which are not sealed or treated, will last a few years.  Untreated hard wooded species, such as Oak, Elm, and Hickory can last three years or more.  The existing soil conditions can also play a role in the longevity of a tree cookie.  Soils higher in organic matter and biological activity will encourage a more rapid decay.
• Wood sealer  Woodworkers often use an end-grain type of sealer or shellac that soaks into the wood fibers.  Or, they may choose a more permanent sealer such as epoxy or varnish.  Materials that soak into the wood will extend the cookie’s durability a few years and highlight the intricate grain patterns.  While materials that seal the wood can extend cookie longevity, just be cautious not to use a material that might leach into the soil and affect nearby plants.  The same is true for wood stains used to expose more of the grain on a lighter color of wood.
• Live or dead trees  Wood from either can be used, but cookies from dead trees may not last as long or look as good unless they are treated, sealed, or wet.
• Oak Wilt  If the tree is in the Red Oak family and died from Oak Wilt in the last year or two, the upper limbs may be used but the trunk section should be burned or buried immediately.  All other oak species are safe to use for cookies.
• Arrangement  Given the many species of trees and sizes as well as the variance in wood color, there are many different potential layout patterns.  A cookie walk with a winding pattern is more attractive and natural than a straight walkway–in most cases.

Tree cookies can be used for many other purposes including coasters, trivets, or even to commemorate your favorite tree.  The various wood grain patterns and colors represent nature’s artwork at its very best.

Tree trimmers in April, 2011 work to extend the Red Oak's life.

 GARLAND (CBSDFW.COM) – When you drive down South Garland Road, you can’t help but notice that a piece of Garland history has been stripped away.

“It’s a living witness to all of what’s occurred in this area,” said arborist Steve Houser. “If it could speak, it would tell us some very interesting stories,” added Houser who spent the last five years trying to extend the life of one of the oldest living trees in North Texas.

The once majestic Shumard Red Oak, however, was eventually reduced to a hollow shell after falling victim to a deadly pathogen. “It invades the root system of the tree, travels up to the base and eventually starts to rot and decay the root system,” explained Houser.

At its peak, the tree located at Garland Memorial Park, stood 70 feet tall and its branches spanned 95 feet wide. The Red Oak was designated a champion which means at one point, it was the largest of its kind in the state.

“It was absolutely heartbreaking to lose it,” said Cecil Williams who is president of the Garland-Mills Cemetery Foundation. Williams said he received some 250 phone calls from distraught admirers of the Red Oak when the tree was being cut down. But Williams said he had no other choice. “We could not have it injure or kill anyone. It’s huge and it had cracks that were leaning over toward Garland Road,” he added.

The tree, estimated to be well over 200 years old, was threatening to topple over onto Garland Road. Houser says it might have lived another three years, if not for this summer’s devastating drought.

The tree will be reduced to a three or four-foot high stump with a wood sealer on top, so visitors can count the tree rings or perhaps even sit on it while visiting a loved one buried at the cemetery.

“Cookiewalks”

A Unique Way to Recycle Your Tree

Within the forces of nature, from death comes life.  As a tree dies in a natural forest condition, it provides many benefits to the ecosystem as it slowly rots, decays, and falls to the forest floor.  It is part of an important natural process that helps to sustain an ecological balance in nature.

Red Cedar Tree walk from a recycled tree.

Have you ever looked under a decaying log lying on the forest floor?  You will find it teaming with life—everything from earthworms, reptiles, and insects, to a congregation of small feeder roots from nearby plants.  A dead tree offers many important types of life-supporting habitats for both plant and animal kingdoms, including a place to live protected from the elements, or the only place you might find moisture during a drought.   

If dead trees are an important part of the natural process, how many snags, as referred to by arborists, are found in your neighborhood?  Although they may be deemed unsightly, they are excellent wildlife habitat and can be left alone if the tree will not damage something (or somebody) should it fall.  Mother Nature prefers that we leave dead trees and fallen branches, but it may not be practical in many urban settings.

Red Cedar stepping tree cookies.

Letting a dead tree stand does not generate income for an arborist; but contrary to conventional thinking, it is undoubtedly in the best interest of our urban ecology.       

Where do dead trees go?  If logs are hauled to our local landfill they ultimately biodegrade, which helps to generate methane gas—an energy source.  That’s not a bad deal, but it may not be the best use for the resource.  If logs are burned, energy is generated but the carbon and other materials stored by the tree throughout its life, are released. 

A Bois d'Arc path recycled from a dead tree.

Communities experiencing a catastrophic loss of trees from hurricanes, ice storms, or tornadoes have created alternative ways to use dead trees.  Remaining tree trunks are carved into artwork.  Limbs are chipped into mulch to replenish the soil.  In some cases, the trunks are milled and converted to furniture, artwork, or other usable objects.  Some wise individuals make exquisite writing pens out of left over wood to raise funds for a worthy cause.

Another option is to use the wood in a way that nature intended by cutting the trunk or larger limbs into “tree cookies”.  Tree cookies are thinly crosscut sections of wood—nature’s version of the concrete stepping-stone.  The cookies can be used to form an informal walkway, using mulch or other materials to hold them in place.

It may look odd at a first glance, but consider that downtown Dallas streets were once paved with thick tree cookies made from bois d’arc trees.  Bois d’arc wood is hard and resistant to rot; therefore, it makes a long-lasting paver.  Likewise, many old houses were built on bois d’arc piers because our ancestors found a good use for what nature provided.

Tree cookies can be sealed or stained on the top side to help retain the wood grain look.  Any sealer on the underside could affect the soil health or plants nearby and is not recommended.  As the cookies start to turn grey, they can blend with the landscape colors or they can be resealed from time to time.  If they are bios d’arc cookies, the wood becomes harder as it dries and they can last a lifetime.     Over time, the cookies will decay.  Just pitch them into your compost pile or cover them with mulch near your favorite tree.

Root hairs that gather under a decaying tree.

Tree cookie walks may be best used in a backyard or areas with limited foot traffic.  They are not ideal for those with limited physical abilities.

Some of the benefits of cookiewalks include:

• Nearby tree and plant roots congregate under the cookies in search of water and the ideal environment. 
• Tree cookies help retain soil moisture and conserve water by reducing irrigation requirements.
• Decaying organic material encourages microbial activity in the soil, which is highly beneficial to nearby trees and plants.
• Once the soil becomes more active, earthworms also appear, further increasing the soil’s fertility. 

Consider planting some tree cookies for future prosperity.

 

 

 

By Bill Seaman
All photos courtesy of Arborilogical Services, Inc.

Texas gardens are blessed to have a large variety of trees suited for our climate and soils.  If there is one group of trees where we might be short-changed, it is the conifers.  In the majority of the state, growing spruce, fir, and balsam is but a pipedream.  Between scorching summers and incompatible soils, many conifers struggle to survive a single season.  Even Japanese black pines, a staple in Texas landscapes since the 1960s, show a steady decline.  Masterfully marketed to be planted in threes, fives, and sevens, few of the odd-numbered plantings remain intact.  This year, we have seen the feathery, grey-green foliage of Leyland cypress turn brown and droop from a combination of heat stress and a fungal disease that has no successful management.  Another conifer is moved from the “To Plant List” to the “Don’t Plant List”.

The silver lining to be found in a year full of horticultural disappointment is to look for those trees, and particularly the conifers, that appear to take the stress unscathed.  They are there if you watch for them.  Some of these trees may seem to be old-hat, but are showing that they are trees that may deserve more respect than what they have been given.  Others are waiting to be discovered for what they can be.

Easily recognized by a combination of peeling and iridescent bark, Arizona Cypress trees create a special interest in the landscape.

Arizona cypress (Cupressus arizonica) best fits the first group.  Native to the Trans-Pecos region of the state, this conifer has worth in a landscape if only for its remarkable bark.  It has an exfoliating trunk that reveals an underlying tissue of copper, bronze and gold–iridescent colors rivaling those found on a butterfly’s wings.  Should you choose to add an Arizona cypress to your landscape, you will need to be patient to see the development of the showy trunk, as it is a moderate grower.

The light blue-green foliage of Arizona Cypress trees planted in the 1930s is giving way to recent cultivar introductions of grey and silver.

However, the nursery industry has rediscovered this tree’s importance, and has selected a number of cultivars based on an assortment of foliage colors that range from silver to blue-grey.  Mature Arizona cypress can be found in residential landscapes and park plantings from the 1930s and 1940s.  While their culture tolerates poor soils, Arizona cypress become their best when planted where drainage is nothing short of excellent.  Likewise, they need full sun from the day they are planted until they mature.

Well adapted to drought and high temperatures, California Incense cedar maintains its bright green foliage.

Waiting to be discovered is California incense cedar (Calocedrus decurrens).  Native to the more arid regions of Oregon, California, and western portions of Nevada, incense cedar is an almost unknown conifer that began proving itself in the Texas landscape more than 100 years ago.  Its bright green, scale-like foliage is soft to the touch, differentiating it from many upright junipers.  When mature, it produces a quirky drooping cone containing a single seed.  The bark is a reddish-brown and deeply furrowed.  In fact, the bark is so stylized, you might think the patterns of twists and turns inspired Van Gogh’s painting style.

California incense cedar is easily identified by its unique bark.

As a testament to its tolerance of extreme weather and pour soils, one of the oldest known incense cedars humbly stands in a Garland, Texas pioneer cemetery.  This tree has held its place for over a century.  California incense cedar is not readily available in garden centers, but nurseries that specialize in unique plants can order them for you.

Early Texas plantsmen recognized the similarities of our climate and soils to those of the European Mediterranean.  The introduction of trees that could adapt in Texas was the logical next step in their grand experiment.  As a result, we have Italian stone pine (Pinus pinea).

This Italian stone pines has developed a broadening canopy large enough to shade this two-story home’s roof and western exposure.

Known for its picturesque silhouette, this pine is suited for the thin rocky soils and infrequent rains that East Texas pines will not tolerate.  Mature Italian stone pines are somewhat lost in the summer urban canopies of San Antonio and Austin, but take their deserved place in the winter landscape.  As they grow, their shape morphs from a loose coned-shaped ornamental to a broad canopied shade tree.  Juvenile growth can be rapid, but the growth rate of mature trees is measured.  Winter hardiness of Italian stone pines has long been a topic of debate.  Young trees produce juvenile foliage of short, single bundled needles, which are completely uncharacteristic of the long paired needles of mature foliage.  It is believed that the juvenile growth does not have the same cold tolerance level as mature growth.  Should that be the case, it would make sense to plant nursery stock that has grown into its mature phase foliage.  Established Italian stone pines do grace Texas landscape as far north as Denton.

While this is only three trees to place on the “To Plant List”, the point is this:  Based on some simple observations, the list of conifers can be much larger than we might have first considered.

Bill Seaman is a sixth generation Texan, degreed horticulturist, and member of the certified arborist team at Arborilogical Services, Inc., “The Experts your Trees Deserve.”

Bryan White, a certified arborist with Arborilogical Services, Inc., was recently interviewed by NBC DFW.

While many other trees show signs of stress, Pecans maintain a dark green canopy and continue producing a fall crop.

It’s unusual to talk about trees without the weather coming up in the conversation.  It is perfectly understandable since much of what we do to care for trees is weather related.  When asked to describe Texas weather, I can sum it up in one word:  Extreme!  This year proves the point—with record cold temperatures in February and unprecedented drought and high temperatures in July and August.  Records have been broken day and night—literally.

This year, I was reminded that our native trees are remarkably tolerant of record-breaking temperatures.  For example, if I only look at the crown of a Pecan tree, and ignore its surroundings, I find nothing unusual.  There may be a few less webworms in the foliage or a few more squirrel-damaged branches.  But the leaves are full and dark green; and this year’s nut crop is maturing as expected and will make up for last year’s poor showing.  Not until I look at a trunk tapering into a ground covered in thin brown grass, and crevasses in the black clay so large earthworms have to take a detour, do I fully realize how well our state tree is adapted to the elements.  That’s when I remember—I already knew that.

As an adaptive coping technique, cottonwood trees drop leaves during periods of drought and extreme heat.

When Cottonwood trees have more leaves under the canopies than in the canopies, the common thought is that these trees are not well adapted to our Texas extremes.  But the contrary is true.  Cottonwoods have immense root systems to support their masts of leaves.  Their roots target every pore space within the tree’s reach, pulling water from the soil.  When the roots can pull no more, a signal is telegraphed to the leaves to jump overboard in order to save the ship.  The leaves yellow and drop.  Cottonwoods place themselves in an induced dormancy in an attempt to live another year.  When the rains come and these massive trees pop out a new set of leaves, I realize how well this native tree has adapted to the elements.  That’s when I remember—I already knew that.

Native Eastern Red Cedars provide food and shelter for birds during periods of extreme heat and drought.

When I see an urban landscape that gets no supplemental water, but contains an old Eastern Red Cedar covered with purple berries and forest green boughs, I think to myself, “How can this be?”  No rain for three months and week after week of 100-plus degree-days, and this tree appears unscathed.  While other trees stress, this Eastern Red Cedar will spend the day providing food and shelter for the neighborhood’s birds.  While other trees struggle until the rains come and the temperatures drop, this native evergreen doesn’t skip a beat.  That’s when I remember—I already knew that.

As an arborist and a tree climber, I rarely pass up an opportunity to place a rope in a large Bur Oak.  Lucky for me, the occasion presents itself frequently.  When recently climbing an unusually large Bur Oak, I noticed the cooling effect as I made my way up.  In addition to being in the shade, I was the beneficiary of nature’s own air conditioner.  The leaves muffled the city noise, and I was eye to eye with the birds.  I thought about all the extremes this native oak had endured for a few hundred years and wondered if, from the perspective of the Bur Oak, our extremes were not extreme at all.  Once I reached the top and found my perch to survey all the treetops as far as I could see, I thought to myself, “I love trees.”  That’s when I remembered—I already knew that.

For all your tree needs Neil Sperry recommends Arborilogical Services, Inc.

Steve Houser, a certified arborist, explains techniques used to climb a tree.