Last week's TreePeople event on Townsend Avenue, up Fiji Hill, which was covered in an Eagle Rock Patch article, has led me to think more about the problems of pubic plantings.

While this column is about the horticultural issues of planting and maintaining trees in public spaces, it would be rude of me not to say a few words about this Jan. 8 event itself. It was great.

The event was masterminded by TreePeople's Yuliana Parada and Marcos Trinidad, who are planning similar events throughout NELA. They chose the site on Townsend because it is where Eagle Rock and Highland Park come together. "This site represents new beginnings for our communities," said Trinidad at the start of the event. "Tree plantings and tree care are the tools we use to make that happen." He later pronounced himself "extremely happy with the turn out and the work that was completed.

The project was to remove heavy reinforced concrete collars from around the roots of each tree as well as posts and ties from their trunks. The idea was to set the trees free.

As Eagle Rock residents know, that section of Townsend is really steep, but lots of good hard work got done last Saturday anyway. A group of citizens that persisted in smiling in the face of those difficulties made major progress in arboreal liberation. And no one rolled away.

As Los Angeles’ fiscal and physical resources dwindle, it is crowds like this one that can save us from real urban blight. In fact, they may have to.

But not my place to blather on about the changing nature of government; this is a column about horticulture.

There are few landscape situations more difficult for a plant than public spaces—just because they are public spaces. Turf gets pounded in our parks. Plants get ridden over, written on, walked over.

Street trees have it toughest of all. Crowded into a small space, surrounded by very compacted soil, and watered when the municipality can afford it.

The two species of trees on this stretch of Townsend are Coast Live Oak and Crepe Myrtle. Both of these trees are tough survivors that fare better than most in street tree conditions.

Generally, they are also staked into the ground. Arborists say this is done to keep the tree from escaping (tree trimming humor, the writer claims no responsibility). It is a humbling testament to the persistence of life that as many street trees thrive as do.

From a horticultural perspective, last Saturday’s workday was attempting to change the living conditions of the trees. The heavy concrete collars were installed originally to protect pedestrians from uneven ground and the trees from the pedestrians. The stakes were put in place to keep the trees from falling over.

But, the trees have outgrown the root collars. In some cases the trunks of the trees were abutting the concrete, in all cases the root room was restricted because the weight of the concrete compacted the soil.

Soil compaction is a major issue in street trees or in trees in high traffic areas for a simple reason: Roots only grow one cell at a time. This greatly limits the energy they can bring to bear breaking new ground.

When tree roots are destructive, it is because they have an opening, like a crack in your old clay sewer pipe. Confronted with heavy soil—and as is the case of the ground under sidewalks, mechanically compacted soil—the growth of the roots is limited.

The root ball stays in the same shape as the original hole. This results in either a stunted tree or, worse, a tree with a large trunk and limited roots. I have seen 40-foot eucalyptus trees uprooted to reveal as their root structure the shape of a five-gallon pot.

TreePeople’s plan is to improve the soil by mulching and aerating around the trees. Stronger roots make for a healthier, safer tree.

Saturday’s project also aimed at removing the “support” stakes from the trees. I put that word in quotation marks because stakes actually serve to weaken the tree far more than they support it. They are more of an obstacle to good tree growth.

Staking is bad for trees in three ways. First, it inhibits movement. Shifting breezes constantly moves trees in natural environments.

From that movement they gain strength. Experiments at UC Davis show that trees allowed to move have better taper, their trunks are larger at the bottom than the top, and are far less likely to fall over.

The second problem with staking is that it creates artificial shade on the trunk of the tree. In nature, when a tree is shaded out by a neighbor, it seeks the sun by growing away from that shade. The same holds true for stakes. When stakes are removed, trees tend to fall straight away from the stake.

Lastly, (and sadly), stakes are rarely removed as the tree grows. The tree winds up being “supported” by a stake half its own diameter—or it simply begins to grow around the stake itself.

Even worse in the staking process are the ties used to secure trees to the stakes. A tree that has ties can entirely grow around the ties, girdling itself, causing it to die. In any case, ties that are not removed will result in a an area weakened because the layer of cambium, which is only a few cells thick and is the highway for the interchange of nutrients from below and energy from above, is constricted.

In most of the cases last Saturday, the stake was embedded in the root system of the tree and was very difficult to remove. In some cases it could not be and had to be cut out.

Both TreePeople and all the volunteers who showed up are to be heartily thanked for the work they did in trying to improve the lives of those trees. The trees will repay that work by giving greater shade, providing more oxygen, and with each year, greater beauty in our community.