Cottonwood Maintenance

Weather: A week ago morning temperatures sometimes were down to the mid-30s. This week, they’ve been in the high 40s and afternoon temperatures have reached the high 80s. Still no seeds have germinated.

Last useful rain: 6/1. Week’s low: 45 degrees F. Week’s high: 95 degrees F in the shade. Smoke from Mexican fires continues to enter area.

What’s blooming in the area: Dr. Huey rootstock, wild pink and hybrid roses, yellow potentilla, catalpa, silver lace vine, Japanese honeysuckle, Arizona yucca, red hot poker, purple locust shrub, Spanish broom, sweet peas, purple salvia, peonies, blue flax, larkspur, snow-in-summer, Jupiter’s beard, golden spur columbine, oriental poppy, yellow yarrow, coreopsis

What’s blooming beyond the walls and fences: Apache plume, Russian olive, tamarix, narrow leaf yucca, showy milkweed, white tufted evening primrose, scarlet bee blossom, tumble mustard, bindweed, green leaf five eyes, fern leaf globe mallow, goat’s heads, alfalfa, fleabane, plains paper flowers, strap leaf aster, goat’s beard, native and common dandelions; needle, rice, three awn, and brome grasses

What’s blooming in my yard: Betty Prior, Dorothy Perkins, rugosa and miniature roses, raspberry, beauty bush, privet, Asiatic lilies, catmints, Johnson’s blue geranium, winecup mallow, smooth and purple beardtongues, Bath pinks, Maltese cross, Dutch clover, coral bells, pink evening primroses, white yarrow, chocolate flower, blanket flower; pansies that wintered over

Bedding Plants: Wax begonia, nicotiana, sweet alyssum, snap dragons

What’s reviving/coming up: Corn is up about 6" in one market garden field; yellow mullein leaves recognizable along one drive

Tasks: Most of the hay fields were cut this week

I made one of my Sisyphean attempts to kill ant hills, especially those of the harvester ants. It’ll last a while, then some queen eggs will hatch somewhere and the small ones will be back. Still I’ve made some progress. Last year I was dealing with more than a hundred hills in my gravel drive. This year, I only treated about fifty.

Animal sightings: Neighbor’s cat, chickadees, gecko, cabbage, sulfur and monarch butterflies, small bees, heard crickets, hornets, mosquitoes, small ants

Weekly update: I planted a cottonless cottonwood in 2004 in the path of a culvert that was fed water from the roof of my neighbor’s house. I hoped that would provide enough moisture.

But trees have a way of creating demands. They respond to water by getting larger, and thus need to have an increased water supply. When a branch broke off the tree in 2013, I assumed it was lack of water, and started running a sprinkler every couple weeks. I wanted to keep it alive, not encourage profligate growth.

Last year leaves turned yellow early on a number of low branches. It had been a hot summer, and I already had increased the watering times. Some of those branches have not come back this year, although most have lots of leaves at their junctures with the trunk.

In February I had man come cut the dead wood. When he was inspecting the tree, he noticed the cut off limb and wondered if I had borers. Cottonwood borers (Plectrodera scalator) are related to locust borers, but a different species of longhorn beetle.

Since he didn’t see any sawdust, he thought I was safe. But doubt was planted. I was told a systemic insecticide was the only thing that handled borers. Since I refuse to mix chemicals, I looked for a dry one that could be sprinkled around the base of the tree.

The insecticide I bought contained imidacloprid. It’s supposed to act like nicotine as a poison. The label said borers, but its inside instructions only mentioned aphids. When I went on-line, I saw the base chemical was good for caterpillars (which are related to butterflies and moths, not beetles). The only borers mentioned were for ashes and elms (of which the less the better). Still, it was the only option.

Rain was forecast for Wednesday, so Tuesday morning I raked all the leaves out from around the cottonwood and sprinkled the insecticide. I ran the sprinkler for about 10 minutes, just in case it didn’t rain. And, of course, the rains never appeared. I ran the sprinkler an hour on Thursday.

Now my problem was how many leaves should I rake back over the bare ground. I had never done much maintenance on the tree. Since the vertical board fence on two sides, a thick layer of leaves had accumulated.

It’s impossible to see the ideal natural environment of these members of the willow family. The various dams built to control flooding and flow have reduced the moisture in bosques. Cottonwoods, which no longer could reproduce, have been replaced by tamarix. Trees that sprouted along irrigation ditches, now have paved roads to channel water toward them. Heavy traffic blows the leaves away.

The cottonwoods that sprouted in an unregulated arroyo have nothing around them but bare sand. They don’t need anything to trap or hold water because water flows through the area whenever it rains.

As near as I can tell, the cottonwoods near the Río Grande grow in grasses that get about a foot high.

In a few places, where dead branches have fallen, leaves have collected. This resembles the condition under my tree where dead winterfat branches have created weirs.

Yesterday, I began cutting out the winterfat, and raking out the leaves, but leaving a thin layer. One thing I know is more leaves will fall in the autumn and the supply will be replenished.

Notes on photographs:
1. Cottonwood (Populus deltoides wislizeni) growing in bosque before Arroyo Seco enters the Río Grande, 23 December 2010. The bosque has responded to the reduced water flows of the river.

2. Cottonwoods growing near the Río Grande within the Española city limits, 14 February 2009. I assume the city removed any dead wood to prevent fires. Thus, the leaves blow away.

3. Leaves trapped by winterfat branches under my cottonwood, 8 June 2019.

4. Cottonwoods growing in an unregulated arroyo near my house, 25 October 2011.

5. Cottonwoods near the Río Grande in the area of Ohkay Owingeh (San Juan Pueblo), 13 February 2013.

6. Cottonwood branches and leaves near the Río Grande, 23 December 2010. This is the same as area as the first picture.

7. Leaves raked over the cottonwood roots, 8 June 2019. They gray is a winterfat that was not removed.