Soaring Cedar Elm

I think that cedar elms (Ulmus crassifolia) are the second most common tree on our property, behind live oaks.

They are deciduous and grow fairly straight, commonly with a single trunk, to an average height of 40 to 50 feet. Their crown's shape is circular to oval and provide nice shade in the summer and a bit of yellow color in the fall. The young trees have wings on the trunk and branches. They are susceptible to Dutch elm disease, but I've never heard of that being a problem around here.

Here's one right beside our garage. It has three trunks but might actually be three different trees growing together. It's shade made a nice spot for our picnic table.

A shady spot

Here's a closeup of a young one further down our driveway to show the wings on the branches.

They have wings!

I took this photo of a particularly impressive specimen along the banks of Onion Creek while on a volunteer project there.

Soaring Cedar Elm

This tree appeared taller than average, probably because it was growing in good, deep soils along the creek. It reminded me of photographs I've seen of redwoods with a straight trunk shooting into the air and branches didn't begin until very high up.

Just Showing Off

I'm always impressed by the tiny lace cacti (Echinocereus reichenbachii) that grow on our property. The Wildflower Center has a nice entry about them.

When they are not in bloom they are hard to see because they don't grow taller than about 6 inches and they are easily hidden by the tall grass. Sometimes they grow in the poorest, rockiest soil where nothing else grows and then they're easily spotted. Sometimes they grow alone but usually they're in clumps.

Their little barrel-shaped bodies are quite beautiful - very regular and geometric. When small, they're almost spherical but they get taller and cylindrical as they get bigger. This one was growing in a wooded area among some rocks. It's only about 1 inch in diameter.

When in bloom, though, you can't miss them - that's why I call them show-offs. It's quite funny to see the tiniest cactus putting out a huge flower. I guess they really need to get noticed by the pollinators.

Here's a clump of five, with one of them in bloom. Do you see them all? The flower is attached to an arm growing out from the main body.

This is a single cactus that produced four flowers at once! A show-off among show-offs! The cactus body is barely visible in the center.

Updraft

Even though we're in a dry period right now there is quite a bit of moisture in the atmosphere. The problem is that it's not falling to the ground!

One of the characteristics of rain in this part of the country is that it's usually scattered and very localized. I might drive through a heavy rainstorm on the way home from work and yet the house got nothing. I reported 3.3 inches of rain at our house for May to our chapter's Rainfall Monitoring Project and a fellow Master Naturalist told me they only received 0.6 inches.

Another characteristic is that because of ground heating during the day, by late afternoon we see the most beautiful, and sometimes, threatening cloud formations. The ground heating causes strong updrafts and as the air's moisture rises and cools, it condenses to form clouds.

Here's a photo of a cloud that I captured in late April. It didn't come over our house - it was moving north if I remember correctly and was east of us.

It's an example of a cumulonimbus cloud formation. They are the largest cloud formations and can form alone or in clusters. They start at a low altitude, typically about 5,000 feet and soar up to 15,000 to 20,000 feet or more. This one has a red tinge along the bottom because of the low, setting sun.

I was disappointed when we didn't get any rain that day. In fact, we only got 0.1 inches in April and that was almost two weeks before this was taken. My attitude toward rain has definitely changed over the years. I used to think that rain ruined the day or weekend. Now I look forward to it and am happy when we get a good drenching. I'd rather see rain spread over several days than getting it all in one burst like we sometimes do, but I'm glad to get it in any form.

A Dry Spell

I've been tracking the rainfall at our house for the last 5 years. I started collecting the data during the Master Naturalist class I took in order to obtain state certification in the program. The data collection is part of our chapter's Rainfall Monitoring Project.

The project divides Hays County in 30 sections, each about six miles wide and seven miles high. Participants report their monthly rainfall and their data is averaged with others in their section and graphed monthly. The project has data back to March 2005. The data will allow us to determine the average rainfall across the county and to see if there are any geographical differences.

You can find the project's results at the link above.

The charts below are the data at our house. The data starts in May 2007 and goes through May 2011. You can see how variable the monthly rainfall is. The annual totals are:

2007 - 28.2 (incomplete)
2008 - 16.4
2009 - 36.7
2010 - 43.1

2011 - 6.9 (so far)

In general, 2007 was a wet year, followed by a dry 2008. 2009 was average and 2010 was wet again. So far 2011 has been dry. The summers tend to be dry, but in July 2007 we had a house record of 12.7 inches.

The data is interesting to me because of my interest in the local habitat. It also affects us directly since rainwater is our house's main water supply. Texas is almost entirely in drought right now. You can view the U.S. Drought Monitor's most recent data here.

I've heard it said that the local rainfall average is 33 inches per year, with most years below average! These graphs may give you an idea of what that means.