Native Plant Feature for February: Mexican/Lindheimer’s Silktassel – Garrya ovata ssp. lindheimeri
Family: Garryaceae/Silktassel family
Written by: Guest Contributor Elenore Goode
Lindheimer’s Silktassel is a valuable evergreen plant to enliven the winter landscape and help wildlife through the leaner seasons. Silktassel is often found in robust, shrubby colonies, but can also grow into small, wiry trees. They tend to grow more slender and tall when in the forest understory, and may be more shrub-like when in the full sun. This subspecies of Garrya ovata is endemic to the Edwards Plateau and grows most frequently in association with the limestones there.
Even during droughts in the shallow rocky soils of rough, steep hill country landscapes, this species proves hardy and dependable for producing berries in the fall that benefit a variety of wildlife. It can tolerate both very dry and wet conditions when in its preferred limestone soils, and loves to grow in forests and their margins, but can be found growing anywhere from along creeks, to the hillsides and cliffs above creeks or moist canyons, to dry hilltop forests or savannahs, and seep areas with shallow calcareous soil.
The berries of Silktassel are a great resource for wildlife in some otherwise stark and eroded landscapes that are often lacking many species of native fruiting shrubs and flowering trees due to historic overbrowsing from livestock, modern vegetation removal, and a lack of decent soils. Silktassel’s slightly fuzzy leaves are a bit more deer-resistant than some native shrubs, leaving more evergreen cover to protect and hide smaller wildlife year-round. Their needs for soil, moisture, and light combine very well in plantings with other native evergreens, such as mountain laurel, yaupon, agarita, and evergreen sumac, which together make some especially beautiful winter cover.
Silktassel’s soothing light green leaf color also contrasts well with the darker greens of these other species, and they have some lovely and intriguing wind-pollinated blooms in the spring. Species of the Silktassel genus are also regarded as having medicinal value. Lindheimer’s Silktassel is becoming more and more common in nurseries, and is an overall wonderful, hardy, and easy-maintenance understory tree or shrub for the native landscape.
How To Build A Cob Wall
By Kirby Fry
After working with natural building materials for 25 years, the cob or “puddled adobe” wall system has become my favorite of all the adobe wall systems. I define a natural building material as one that is locally available and non-manufactured. This how to do it yourself guide will describe 4 different forms of adobe wall systems, explain why the cob wall system is my top pick, and tell you how to build a cob wall.
Types Of Adobe Wall Systems
Adobe is generally made from sand, clay and straw. Adobe wall systems include handmade adobe blocks, compressed earth blocks (engineered adobe), earth bags (flex form adobe), and cob (puddled adobe).
The handmade adobe block is perhaps the most traditional system for building an adobe wall. It is made from sand, clay and straw. Fresh, clean horse manure is often substituted for the straw component. Adobe blocks are 10” wide by 14” long by 3 ¾” tall. A clay slip is applied between each course of adobes. The adobe block wall system can be either 10” thick or 14” thick.
Compressed earth blocks (CEB’s) do not have to have straw in them, and are made by a machine that compresses moist sand and clay at a pressure of 1,200 to 1,600 pounds per square inch. Often 6% of the mix is portland cement to keep the CEB’s from eroding during the construction process. CEB dimensions are the same as the handmade adobe block, 10” wide by 14” long by 3 ¾” tall.
Earthbag wall systems are also referred to as flex form adobe or superadobe. This method includes mixing sand and clay together, getting it moist, and packing it into continuous bags. Earthbag walls are about 16” thick. When this method was first developed by the Iranian-born architect Nader Khalili he was using a solid nylon or plastic bag, now earthbag builders have gone over to using the Raschel weave continuous onion bag that you commonly see being used to sell onions in at almost every grocery store.
Cob or puddled adobe wall systems are made from sand, clay, and straw that is mixed together and then dumped on top of the wall system. Cob is an old English word that means “lump of dough” and because it is put into the wall system while still wet, the builders can only raise the walls up 4” or 8” per day before it begins to slump. A cob wall may vary in width from 12” to 18” depending on how tall or long the wall is.
Why Cob Is My Favorite Adobe Wall System
After working with all of these adobe wall systems my favorite is now cob, and here’s why:
The cob wall system is monolithic and does not require a concrete bond beam at the top of it – a bond beam is made from concrete, steel, or wood and in adobe block and CEB wall systems a bond beam is necessary to hold the top of the wall system together.
The cob wall system is ready to plaster when it is finished. Earth bag, and CEB wall systems require more preparation for plasters like filling in between the bags, and or chipping up the face of the CEB’s.
The cob wall system is more efficient for smaller job sites. Making 5,000 to 10,000 adobes or CEB’s all at once on a job site is a big logistical chore and requires a lot of space. Making adobes off site and hauling them to the job site is also a huge logistical chore. Making cob on site is slower, but requires less space, and makes less of a mess.
Lastly, cob wall systems are a more ergonomic building material for the builders. The cob is easily dumped out onto the wall system a half bucket at a time. Ladders and scaffolding keep the crew working between their knee and chest heights. By contrast, filling earthbags means that you are standing on top of the wall system, holding a 5 gallon bucket with the continuous earthbag attached to it, walking backwards on top of wet adobe under your feet while 2 or 3 people dump the fresh adobe into your bucket.
How To Build A Cob Wall System
All buildings require a solid foundation, and the immense weight of an adobe wall system is no exception to that rule. Traditionally for a 14” wide cob wall system an 18” wide by 24” deep rubble filled trench with a concrete or mortared-together masonry footer has been used. Today, I wouldn’t hesitate to pour an engineered concrete slab for building a cob wall on top of.
I highly recommend that the roof for any natural building be a hip roof where there are protective eves on all four sides of the building. A single gable roof leaves 2 sides of the walls exposed to catching more weather which can significantly damage lime and clay plasters.
Keep your cob wall system relatively low, somewhere between 8’ and 12’ tall. A second story on top of a cab wall is possible, but above 8’ to 12’ in wall height, I recommend going over to a more conventional 2” x 4” stick frame.
Once the grade beam or concrete slab has been constructed, it’s time to have the materials delivered to the site. Here is what you will need to begin; 10 yards of manufactured sand, 10 yards of clay, 10 yards of decomposed granite, and 12 straw bales. These materials need to be close to the work site, and you need to be ready to have more truckloads of material brought in again and again in the proper order.
On smaller job sites our crews mix cob on a 4’ by 4’ plywood mixing board with a mortar hoe. Initially we were mixing the cob on blue tarps but after just 2 weeks the tarps fell apart and everyone on the crew preferred the mixing boards anyway. On a bigger job site a large gas powered mortar mixer is the only mixer that will turn over the heavy cob. Some crews will also use a skid steer loader with a mixer attachment but I have never used one of those before.
So let’s start our first batch of cob with a ratio of 1 to 1 to 1. That’s 1 half bucket of clay, one half bucket of manufactured sand, and 1 half bucket of decomposed granite. The straw is chopped up into 6” to 10” lengths with a machete on a board and 4 large handfuls will be added into each mix. First dry mix the clay, manufactured sand, and decomposed granite. When all of those ingredients are thoroughly mixed together in dry form, then add about 4” to 6” of water in a 5 gallon bucket to the dry mix. Next, wet mix those ingredients. When all of those ingredients are thoroughly mixed together add 2 large handfuls of chopped up straw. When all of those ingredients are thoroughly mixed together add 2 more large handfuls of chopped straw (total of 4 large handfuls) to get the final batch of finished cob.[Images 10 through 18 show how the cob ingredients are added to and mixed on a 4’ x 4’ mixing board]
Load the cob into 5 gallon buckets filled only half way. Never fill a bucket up all the way as it becomes too heavy. Always try to carry a half filled bucket in each hand so as not to strain one arm by carrying just one bucket at a time. Dump the half full buckets of cob directly on to the wall system and begin to evenly work the cob out onto the wall system. Press the fresh wet cob down onto the foundation or onto the dried cob beneath it by using a cobber’s thumb, which is usually just a 1” diameter by 10” long branch or old tool handle. The aggregate in the cob is deliberately sharp and will quickly tear up your hands and fingers if a cobber’s thumb is not used.
If the cob is dry enough, one should be able to build 4” to 8” in height of cob wall per day. When the cob begins to slump, it’s time to stop adding material to it. The next day, yesterday’s slumped cob will need to be trimmed off and reused. Every morning, without exception, the cob wall will need to be trimmed, and the wall system kept square and plumb.
Wooden door and window frames called “bucks” will need to be framed and set flush to the exterior of the cob wall. A 3’ 0” wide by 6’ 8” tall standard exterior door should have a door buck with dimensions of 3’ 2” wide by 6’ 10” tall by 4 ⅝” deep. A 2’ 6” wide by 5’ 0” tall standard window should have a window buck with dimensions of 2’ 6 ½” wide by 5’ ½” tall by 4 ⅝” deep. The window bucks are typically set at a height of 6’ 8” and down in order to match door heights, and are held in place with wooden cleats or pegs attached to their sides called “dead men.” The doors and windows themselves will be set into the bucks after all of the cobbing has been finished.
A structural header or piece of timber framing is set over the door and window bucks to carry the load of the cob wall above it.
When the cob wall reaches its final height a simple top plate, not a concrete bond beam, is embedded into the wall using more wooden cleats or “dead men.” The roof’s rafters will sit on this top plate.
The electrical wiring is notched into the wall system after the cob wall is built. This cob building was permitted and inspected by the City of Austin and the city required this method of wiring because it did not want the wiring to be buried behind the cob allowing them to visually inspect it.
The exterior walls were plastered with a lime plaster and the interior walls were plastered with a clay plaster.
My advice to anyone building with cob for the first time is to start on a small scale. Building with natural building materials requires just as much, if not more, skill and caution than building with conventional building materials. It will also require more time than building with conventional building materials, and cost about 30% more.
Do not be daunted by these suggestions and warnings though, the rewards of living in a home made from natural building materials and or that you have built yourself are infinite and your life will change for the better because of it!
We’d like to wish all of you a very happy holiday season & extend a very sincere thank you for your continued support of our mission!
In the new year, we will be publishing The Dirt on a quarterly basis. We would love your input on which stories you want to see focused on going forward. Please take a moment to respond to this poll and let us know!
Read more below for a few end-of-the-year seasonal tips. As always, if you wish to make a donation to Earth Repair Corps, it’s tax-deductible.
- One of our favorite native plants of the holiday season is the evergreen shrub/small tree Yaupon (ilex vomitoria), also known as Native Holly.
- The red berries that yaupon produces in the winter make for great seasonal decorations, and are also welcome winter forage to local wildlife.
- Yaupon is the only caffeinated plant native to North America, and its leaves can be used to make a tea by roasting them at a low temperature. Check out some of these recipes so you can roast your own!
- Yaupon can be found across east Texas, and into the eastern portion of the Hill Country. Read more at Forage Texas.
- Possumhaw (ilex decidua) is very similar to yaupon, but it is not evergreen and loses its leaves in the winter.
- Winter is always a good time to plant cover crops. Rye, oats, and wheat can still be sown throughout the season. Brassica and other winter greens can also be planted if the seedlings were not hit by hard freezes.
- There are several ways to reduce your waste during the holiday season. Whether it’s with food scraps, gift wrapping, or discarding of your Christmas tree, don’t forget to apply permaculture principles post-celebration!
- Local herbs for digestion: the holiday season is typically characterized by an abundance of food, and you may find yourself wanting some digestive aids. Take a look at Chickweed, Curled Dock, and Dandelion. And this recipe for an Evergreen Cordial by Traditional Medicinals just for fun.
Wishing an abundant holiday season to you all!
Featured Tool – Seymour, Kenyon 14-inch Bow Rake With Aluminum Handle
Written by: Kirby Fry – Photo by: Elenore Goode
I’ve gone through a lot of bow rakes over the past 20 year and up until recently, I could only tell you what I didn’t like about them – the fiberglass handled rakes crack and split, the wooden handled rakes are heavy and frequently have the rake head detach.
Not too long ago, however, I was at Ewing Irrigation & Landscape Supply and spotted a very interesting looking rake. It had an aluminum handle which was light and strong and the rake head itself was welded and riveted onto the handle. There was one that was 17 inches wide and one that was 14 inches wide. I eventually bought both of them, but especially liked the 14 inch rake because the narrower rake is really good for tough jobs where the material you’re moving is heavy, inconsistent in size, and in large clumps.
It’s the first rake I reach for on a job site or at a permablitz.
The handle is 60” long, aluminum, and powder coated. It is strong, flexible, and durable. The rake is 14 inches wide with 13 tines, and is welded and riveted to the handle.
This bow rake has never even come close to failing me.
October 2019 – Native Plant of the Month
Written by Guest Contributor: Elenore Goode
Plant: Asters/Symphyotrichum genus species
Focusing on a few of the most common species for central Texas: Fall Aster/Symphyotrichum oblongifolium, Drummond’s Aster/Symphyotrichum drummondii var. texanum, Tall Aster/Symphyotrichum praeltum var. praealtum, White Heath Aster/Symphyotrichum ericoides
Fall flowers are a soothing reprieve after the stifling summer heat, and a vital necessity for many creatures that are preparing for migration or winter.
Drummond’s or Texas Aster
Fall Aster is perhaps the most well-known and ubiquitous of this genus in central TX, and with it’s manageable and small woody shrub-like form and happy demeanor, it is an essential garden plant for the hardy native landscape. Fall Asters spread well through their roots to form wide colonies, though not as vigorous a spreader as Tall Aster, and a bit hardier. Their habits, needs, and their radiant bunches of little purple flowers compliment very well with other fall blooming native plants. Their roots are also easy to transplant to make a whole new patch, and their above-ground structure is often better able to infiltrate rainfall into the soil than some asters – some of the other species are really meant to grow in a prairie-like matrix with the surface structures and roots of many other species filling in the gaps for the other, as well as providing physical support. Every species has its strong points, and by combining as many plants of complimentary growing habit together as possible, we can allow for stronger roots systems that soak in more rainfall, feed a more diverse group of soil micro-organisms, and create a more resilient and complex layer of nutrient-rich humus comprised from the various qualities of all the different types of leaves.
Featured Woodlot Tree – October 2019
Common Name: Southern Live Oak – Species: Quercus virginiana – Family: Fagaceae
Written by: Kirby Fry – Photo by: Elenore Goode
“The best time to plant a tree was 20 years ago. The second best time is now.” Chinese proverb.
Live oak trees are iconic trees here in Central Texas, they are evergreen, extremely strong, and make beautiful and effective shade trees. The first tree house I built was in a live oak tree in our backyard. The tree house was three stories tall with operable doors and windows, carpeting, and electricity. It took three of my friends to wrap our arms around its trunk.
If you could plant a tree and see it thrive, which one (or ones) would it be? I would plant a live oak, a magnolia tree, and a bald cypress. We should continue on with our plans to plant forests and woodlots that we can build houses with, that function as windbreaks and erosion control, and that enrich natural regions.
Which trees and timber products do we need the most? Let’s take a stroll down the lumber aisles of any Home Depot, Lowe’s, or McCoy’s. There we find framing lumber milled from spruce, pine, and fir. The next aisle over we find sheets of plywood made from pine, oak, birch, and maple. The next aisle over we find trim boards made from oak, cedar, pine, and poplar. Visit a specialty lumber store and you find oak, cypress, ash, maple, and mesquite among many others for furniture, cabinetry, and countertop production. Not all of these species of trees can be grown here in Texas but many of them can.
In a sustainable human settlement, one management objective would be to plant enough trees to replace the lumber used to build your home. A 1,000 square foot home requires approximately 6,300 board feet to complete. A mature pine tree at a height of 80 feet and width 2 feet will yield 754 board feet, so 8 or 9 mature pine trees are what we need to build a 1,000 square foot home.
Each tree species grows into a different form and will vary on how many board feet it yields when mature, so a woodlot consists of a variety of different trees – oak, pine, cypress, ash, maple, and hickory, and those trees are used for a variety of different functions in the house – framing, planks, trim, and doors and windows.
The southern live oak tree has historically been used for ship building (because its trunk and mature branches are curved), and tool handles. It can also be milled into posts and beams, and lumber for trim.
The acorns from live oak trees should be collected in late October as they begin to fall from the tree, and then be planted directly into the ground. The best acorns for germinating will still be on the tree. The larger the acorn, the more likely successful germination will be. Remove the acorn caps and any other debris, put the acorns in a bowl of water and discard the ones that float because the shell has been breached and air has gotten inside of it.
Sow the acorns in good, well-drained mineral / sandy soil with a 1 inch layer of compost on top. The acorns will not need cold treatment or stratification. Partial shade on the west side is helpful, and moderate, consistent watering is essential. Squirrel proof caging or exclosure for the seedlings is recommended.
Transplant your live oaks in the early spring. Prune the roots of the tree to make transplanting easier and encourage a flush of new root growth closer to the root ball. A wide shallow hole is best for live oaks. Water moderately and consistently for the first year, and do not add soil amendments or fertilizers. Keep the top of the root crown 1 to 2 inches above the surface of the ground.
Pruning & Maintenance
As your live oak grows, moderate branch pruning is recommended, removing just the lower branches to ensure a knot free trunk up to about 8 or 10 feet in height. Proper wound care is required by minimizing the number of branches pruned back each year – 3 to 9, keeping the pruning cuts to the smallest diameter possible, and spraying a pruning tar on open cuts and wounds to prevent fungal infection.
The live oak tree will be mature in 50 years, however in a woodlot your cultivated trees are harvested at earlier stages in their life cycle for fence posts, tool handles, and smaller posts and beams.
September 2019 – Native Plant of the Month
Written by Guest Contributor: Elenore Goode
Goldenrod/Solidago spp., Solidago canadensis/Tall Goldenrod
Late summer in Texas is a tough time for a plant to begin to flower, and the many perennial species of Solidago that grow across the state are some of the most dependable plants for wildlife to find blooms on at this time, despite any heat and drought. Growing everywhere from wetlands and prairies to drylands and cliff faces, Goldenrods are a very adaptable and diverse genus of plants that have much to offer humans and wildlife. The different species also have a variety of growth habits, from small clumping species, to some that will spread quickly through their roots, and go as far as they can reach.
Their bright yellow hues are a welcome sight for pollinators at the end of a tough summer. Goldenrods can be counted on to tough out the worst and still show their best colors. Solidago blooms are often super loaded with a great variety of pollinator species buzzing around them, since they provide a vital surge of rich pollinator forage at a time when many insects and other plants may be trying to recover from a harsh summer before winter.
Goldenrod’s flowers and leaves have also long been recognized as having useful medicinal qualities, and remain popular as a hardy wild remedy plant in many pollinator gardens.
The drought endurance, ability to grow in poor conditions, and rapid-spreading habit of some species may also make them too vigorous for companion planting in vegetable and herb gardens. However, these same qualities make those species ideal for re-vegetating ecologically-degraded areas with beneficial plants for wildlife, and are a great choice for areas with poor soils and low species density. Even in gardens, they can be carefully introduced (especially in more depleted soils that need organic matter) and used to suppress other plants like Bermuda grass, or to provide just enough shade for herbs and veggies in late summer, when not allowed to smother them.
These hardy but aggressive species of Goldenrod are great as support plants, and excel in wildflower borders, hedges, and tall grass prairie settings. They do best when they are allowed to grow in dense colonies, or with other tallgrass prairie plants for structural support.
September 2019 – Crop of the Month
Pecan – Scientific Name: Carya illinoinensis
Written by: Kirby Fry
The pecan tree is iconic. It is a tall, beautiful and agriculturally productive native tree.
The pecan tree is also the state tree of Texas.
Since the 1880’s the United States of America has become a major producer of pecan nuts, which are actually drupes or stone fruits, harvesting 264.2 million pounds of pecans annually as of 2014. Mexico and the US of A account for 93% ton of the world’s pecan production.
Growing up in Houston, Texas, my second story bedroom was perched over our neighbor’s single story house which had a metal roof on it. I remember hearing pecans falling from their pecan tree and hitting that roof all throughout the fall. During those fall and winter months there was also a wooden bowl that sat out in our dining room which was full of pecans. Nearby was an assortment of tools used for cracking open the shells and picking out the delicious fruit inside, we had contests to see who could “shell” the most intact pecans.
Right around the fall equinox, pecans are ripening here in Texas. This is a really good time to start thinking about planting your very own pecan trees.
The pecan tree can be planted from late December through early March and will do well in every county of Texas. They are typically sold as bare root stock with a 24” to 32” long intact tap root.
The roots of a pecan tree should be kept moist from the time of purchase to the time of planting.
At least 2 or 3 different varieties should be selected and purchased for cross pollination.
Cultivar pecan trees are grafted and chosen for the sweetness of their fruit, the thinness of their shell, and the alternating years that they produce. Pecan tree growers are careful to select trees that yield pecans during alternating years, as a pecan tree will produce one year and then possibly skip 1 or 2 years of production.
Several varieties of pecan trees are recommended for Central Texas. These varieties include – Sioux, Choctaw, Wichita, Cheyenne, Pawnee, Forkert, Cape Fear, Kiowa, and Caddo. They have all adapted to river and creek bottoms, preferring deep well drained sandy and loamy soils, though I have also seen them do well in clayey soils that have good drainage.
Select a site to plant your pecan trees that is at least 20’ away from your house, and away from driveways where cars will be parked. Pecans are large trees that tend to start dropping large branches after 20 or 30 years of growth. If planted close to your home, they will need careful pruning later on in their life cycle.
Pecan trees should be planted 35’ apart from one another in order to give their massive root systems plenty of room to develop.
The hole you dig for them should be as deep as the tap root is long (sometimes 32” to 48” deep), with the objective being to replant the tree as deeply as it was planted at the nursery. The soil line on bare root trees can be determined by the color of the bark.
Because the hole you will need to dig for a pecan tree will be deeper and larger than most fruiting trees, the tap root should sit firmly against the bottom of the hole you dig to avoid undesirable settling. The hole should be carefully back-filled and watered in, in order to prevent branching roots from settling or sinking too much as well.
The tree should be watered in with at least 5 gallons of water per tree immediately after planting.
The time needed for the tree to begin production takes close to 8 years, after which the tree will begin to yield 10 pounds of pecans per year and up.
Tree Fertilization and Maintenance
A nitrogen fertilizer should be the only soil-applied amendment that your pecans need. Alfalfa meal, feather meal, bone meal, and/or blood meal should be applied in small amounts throughout the growing season. These are low or moderate sources of nitrogen and you could easily double the amount applied when compared to high nitrogen fertilizers.
About 1 pound of high nitrogen fertilizer (21-0-0) per inch of trunk diameter should be applied each year. Keep high nitrogen fertilizers away from the base of the trunk in order to prevent tissue scalding.
As the trees mature into their 7th or 8th years of growth, avoid applying high nitrogen fertilizers after June in order to prevent a flush of new growth getting frozen back in the fall.
During the first 7 years of growth, a zinc nitrate solution should be applied in a liquid form to the surface of the leaves, 2 to 4 teaspoons per gallon of water or 1 to 2 quarts per 100 gallons of water. Pecan trees deficient in zinc will have smaller, weaker leaves and leaf stems and in extreme zinc deficiencies the trees will experience a higher rate of die back during harsh summer and winter conditions. This zinc emulsion should be sprayed on the trees every 2 weeks or so during the growing season.
Water your pecan trees from March through September for the first couple of years after you plant them. During the summer time your young pecan trees may need 2” of water per square foot of growing area, one time per week.
Low emerging braches (a.k.a. trashy trunk) should be pruned back each winter, and care should be taken to select and preserve a central leader for the top of the tree. Try to avoid allowing a “V” to form in the tree’s trunk as pecans grow to be large and somewhat brittle, and a forked trunk will often crack and split.
Maintain the area under your pecan trees and keep it free of brush and tall grasses during the fall so that the fallen pecans can be more easily harvested. Once your pecan trees are established after 8 years or so, fertilize and water only as needed.
Harvesting pecans is a great way to supplement your fall and winter diet. Pecans also have a high market value and can be used to feed pigs during fall and winter months.
Take a look at your property, and find a good place to plant a few pecan trees.
Featured Tool – Self-Leveling Rotary Laser Level
Written by: Kirby Fry
All photos © Elenore Goode 2019
This Bosch laser level is an entry level tool and can be purchased at most Home Depots for $499.00. It is self levelling, and has a range of 800 feet.
Who would need one of these tools? Builders and surveyors. The level has all sorts of applications. In the field we use it to survey conservation terraces, ponds, and to measure grades or elevation changes on slopes for locating roads and driveways. On the construction job site we can use the same level for determining the elevations of siding, doors, and windows.
The instruments I’ve used in the past started out as primitive, time consuming, and imprecise. In the US Peace Corps we used a simple A-frame with a plumb bob on it. Then for years I used a bunyip water level, or clear tubing filled with water attached to 2 yard sticks. My first laser level was a CST Burger rotary laser level but it was not self-leveling.
During our recent permaculture design course we used all 3 tools – the A-frame, bunyip, and laser level, and gave students the opportunity to experience a wide range of tools used to determine level and measure changes in grades.
Now I use the Bosch Self-Levelling Rotary Laser Level and there’s no going back to the more primitive tools unless I’m in a pinch. Laser levels can also be rented.
August 2019 – Native Plant of the Month
Written by Guest Contributor: Elenore Goode
Escarpment Black Cherry – Prunus serotina var. eximia
Escarpment Black Cherry is a beautiful and unique regional variety of Prunus serotina that is endemic to the Hill Country and south central Texas. Prunus serotina var. eximia is a great tree for wildlife, and is delightful-looking year round and as it changes through maturity – from its narrow, tall form as a young tree, to its fragrant early spring blooms that are beloved by bees, the refreshingly lush green foliage, the small and edible cherries (black when ripe, but the pit and wilted leaves are toxic), the crisp yellow fall colors, and the intricate and changing patterns of the bark, which is also traditionally used to make medicine.
While mostly smaller specimens are left after centuries of deforestation combined with over-browsing of saplings, there are still great 40-50+ foot Escarpment Black Cherry trees here and there. These are remarkably hardy trees that will survive severe drought through dying back to their roots and going dormant. Though very hardy, in order to truly thrive to their potential they need slightly more moisture than the average hill country tree, and can grow into beautiful large trees that make dense shade when they have good soil, ample water, and close to full sun, but with the shade of other trees or a hill.
Almost all large remaining cherries are in a moist canyon or on a north-facing slope with good forest cover around them, creating deep shade, which helps to conserve moisture in the soil when it is most needed!
Once we’re in the midst of summer, we can fully appreciate the cooling value of the native forests of Texas, and so do all the plants and animals! Creek and rivers here greatly benefit from tall tree shade as well, since it reduces evaporation and keeps water temperatures at livable levels for aquatic wildlife. Historically, most of the Hill Country’s steep slopes and hills were forested in old growth woodland, and the individuals trees were much larger, with a tall expansive canopy that shielded many more sensitive understory plants and the soil from the intense heat. Due to the loss of soil health, depth, and its microorganism connectivity, it is much harder for slightly needier native trees like these to survive across much their historic range, so these cherries are often found as a small understory tree growing in the shade and nicer soils produced by oak trees, due to the lack of remaining suitable habitat. Tiers of canopy shade are a necessary part of the native ecology of the Hill Country, and are how most woody species here grew together, as described by those who saw this region before it was largely deforested by 1860. Many native trees do not like to spend their youth in the full sun, where the harsh sun rays cause them to spend most of their energy respirating, rather than use the energy to grow. They also do not like their soil and root area exposed to bake in the sun instead of growing in the deep, spongy, humus and moisture-rich forest leaf mulch they should have.
A common and unfortunate myth in Texas is that native grasses do not grow under trees – which has really only come about from the short-sighted observation that in overgrazed pastures where all the grass was killed and thus woody vegetation begins to fill the created void of life, there often will still be little grass once trees re-vegetate the area – because there wasn’t really much left before… Yet we can’t make such claims and scapegoat trees for centuries of poor land management if we spend enough time with the native grasses in their less-disturbed habitats.
Many great native grasses love to grow in at least partial shade, including eastern gama, bristlegrasses, indiangrass, setaria, inland seaoats, wildryes, etc. It would be beneficial for more ranchers to encourage and utilize shade pastures for summer forage, since the same grass in shade vs sun might still be green and growing vs dry and shriveling in the dryness of late summer. In many upland areas, the remnants of the big native bunch grasses (that are now mostly restricted to riparian areas and lowlands) cling on to life often only by the protection and partial shade of trees – just shielding plants from the later afternoon sun goes a long way in making it possible for them to survive tougher soil and moisture conditions.
Full sun is more bearable to plants in Texas when they have deep soils and good moisture – and the loss of these things from the erosion and dehydration of this region means that shade and trees, and the positive feedback loops they create towards a more moist environment, are more important than ever!