Draining or Retaining? Fungus Gnats and Other Side Effects of Poor Drainage

Southwest Yard & Garden by Dr. Marisa Thompson "The drainage rate of any soil is also influenced by the drainage rate of the soil lower in the profile... To understand soil drainage one must investigate the total profile." - the Internation Society of Arboriculture and Urban Tree Foundation "Planting Standards

Question: I’ve been battling with little gnats in potted plants for months. I have covered the soil with small aquarium gravel, and have tried using bowls of vinegar and even sticky flytraps. But they are still very prevalent in my home and making me a little bit nuts! -Erin F., Albuquerque, NM Answer: It sounds like you have fungus gnats. As Dr. Carol Sutherland, NMSU Extension Entomologist and State Entomologist for NMDA, explained, “Fungus gnats are those very tiny, blackish, mosquito-like creatures that fly in your face when you water your plants indoors. Female fungus gnats are attracted to the organic matter in your potting medium. Algae, fungi, and va…

Grow Your Library: Recommended Plant Books

Southwest Yard & Garden by Dr. Marisa Thompson

Question: We are building our Extension Master Gardener library. What are your favorite plant books? -Lin Y., Valencia County, NM Answer: I try to keep an edition—any edition—of Robert DeWitt Ivey’s “Flowering Plants of New Mexico” with me as I travel around the state. Every plant in the book includes a hand-drawn image of the flowering structures and leaves, and a zoomed-in portion of the plant if there are distinguishing characteristics to be found. In the introduction, Ivey explains that he made most of the drawings from fresh or live plants during their flowering period and includes the location and date. A miniature map of New Mexico also accompanies each drawing with a shaded area depicting the general distribution range. Call me crazy, but when you see a beautiful flower on a hiking trail near Cloudcroft on July 4 and then find it in this book with Ivey’s note saying he found it in bloom on July 16 in the same national forest, you m…

Saltcedar Eradication Takes Patience and Persistence

Southwest Yard & Garden by Dr. Marisa Thompson Guest author: Dr. Leslie Beck, NMSU Extension Weed Specialist

I have a saltcedar I inherited when I moved into my rental home in Zuni, NM. I have cut it back to a stump as best I could without a chainsaw or any power tools, but it incessantly puts out shoots and tries to stage a comeback. What is the simplest way to permanently kill this invasive beast? -Tammy P., Zuni, NM Answer: You are not alone in your saltcedar frustrations. I invited NMSU Extension Weed Specialist, Dr. Leslie Beck, to review your options:
“Saltcedar is a highly invasive and difficult-to-control noxious weed throughout the Southwestern states. Many of its growth characteristics contribute to its difficult management, most notably the primary root system, which can penetrate more than 30 feet deep in the soil, and aggressive lateral rhizomes that are responsible for many of the shoots that return after cutting. The plant crown (where the main body of the plant …

Osmotic Pressure Inside Nectarines Forced Sap to Ooze Delicately and then the Wind Whipped It Around

Southwest Yard & Garden by Dr. Marisa Thompson
Question: What’s the deal with these clear, stiff, noodle-like formations on my nectarines? Have you ever seen anything like this? -Amos A., Albuquerque, NM UPDATE: Amos reported that he tasted the ooze and it had no particular flavor. More updates expected as fruit ripen. Figure 1. Sap exudate oozing out of these nectarines was whipped around by the wind before it had a chance to dry and solidify, making extremely rare decorative formations (photo credit A. Arber).
Answer: Wow, I have never seen anything like this before! However, I’m only on month ten as the state Extension Horticulture Specialist for NMSU, and I have never grown nectarines before, so I shared your strange photos with several experts from around the state. All agree that the images show extremely rare, spiraling strands of hardened nectarine sap, but there’s no real cause for alarm or recommended action. NMSU Bernalillo County Extension Horticulture Agent, Sara Moran, sugg…

Old Trees Deserve Extra Care: They Cannot Live Forever, but You can Help them Live Longer!

Southwest Yard & Garden by Dr. Marisa Thompson Question: Are trees immortal? -2nd Grade Student at La Promesa Elementary, Veguita, NM Answer: Sadly, no. Even under the best possible circumstances, trees cannot live forever. Many trees can have impressively long lifespans, though. Of the top four oldest documented trees in New Mexico, one of them is right there near you in Socorro County: a Chihuahua white pine in the San Mateo Mountains that is over 600 years old. The others are a Douglas fir at El Malpais that is about 1,275 years old, a limber pine about 1,670 years old, and a Rocky Mountain juniper at over 1,900 years old. One famous old tree was another Douglas fir near Grants named Yoda that was known to be over 650 years old and was only 7 feet tall. Yoda died in 2014, and the documented cause of death was a combination of increased temperatures and drought. Notice anything that those trees have in common? They are all evergreen trees. In fact, on a list of old trees published by …

You Can Help Avoid Plant Sunburn

Southwest Yard & Garden by Dr. Marisa Thompson Reprint from June 2010. Written by Dr. Curtis Smith, retired NMSU Extension Horticulture Specialist, with additions by Marisa Thompson. 
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Through Thick and Thin: Managing Fruit Load on Backyard Trees

Southwest Yard & Garden by Dr. Marisa Thompson ~45 second video explaining how we started thinning a peach tree in Bosque Farms.

Question: Several branches on my peach tree are hanging lower and lower as the peaches get bigger. Is this OK or should I be thinning the fruit? -Carol B., Los Lunas, NM Answer: On the one hand, you don’t want to thin your peach tree too soon and then lose the fruit you saved to a late frost or the dreaded hail storm. On the other hand, reducing the fruit load on heavily bearing branches has major benefits. First of all, the branches you’re describing that are hanging lower as the peaches develop are in danger of breaking. If the weight of the fruit just bends the branch, a strong gust of wind can be the final straw. And “breaking” is a kind word. Often, it’s more of a terrible rip-like tear that can damage the main trunk irreparably. Pruning back longer branches earlier in the year, ideally when the trees are still dormant, can help with overall structure and…