Showing posts from September, 2017

Dodder: To Kill or Not to Kill

Southwest Yard & Garden | September 23, 2017

What are the beautiful golden strands that show up from nowhere, and seem to attack the goatheads? Can they be moved from one patch to another where it is not growing yet?

B. Stanley, Chaparral, NM

In order to fully address your question, I have consulted with NMSU Weed Specialist, Dr. Leslie Beck. Those golden strands are from a climbing parasitic plant commonly known as dodder of the genus Cuscuta.  It is a close relative of morningglory and the dreaded field bindweed, which are all in the plant family Convolvulaceae. You may have seen time-lapse video footage of vine tips making slow, circular, swaying motions as a way of searching for sturdy branch to climb. Dodder grows in a similar way. Dodder germinates from seed in the soil during the hottest, wettest point in the summer. Once it germinates it immediately searches for a host. A particular favorite is puncturevine (also known as ‘goatheads’) which was the subject of l…

Get Your Goat(heads): Control Puncturevine Before it Controls You

Southwest Yard & Garden | September 16, 2017

Question: How can you get rid of those awful, nasty goatheads? Last year it seems I was able to control them but this year they are so plentiful that I must seek help. HELP!

J. Melcher, Tularosa, Otero County, NM

Answer: You are not the only one with a goathead problem this season.  I have received several pleas this month for extra information about these persistent and painful weeds. Stepping on a goathead can be very distressing and provoke the use of colorful language along with prolonged limping.

Once the environmental conditions are just right they ‘grow like gangbusters’ and are very difficult to control. Before you attack, look closely to see what stage of growth the plants are in. If the flowers are not yet formed or are still developing you can stop the life cycle by hoeing and leaving the green leafy part to die a slow, hot death. I recommend you pop them up out of the soil with a hula hoe (also called a scuffle or stirrup hoe).…

Fall Webworms

Southwest Yard and Garden: Fall Webworms


What are these caterpillar-filled white web masses on branches of my apple and walnut trees? And what should I do to control them?
- Gardener in Sierra County

From your photos, it looks like you have a broadleaf tree pest that is common at this time of year: fall webworms (Hyphantria cunea).  These fall webworms make white nets shaped like bags covering branch tips and if you get close enough you can see those caterpillars hanging out inside. 

The larvae of fall webworms look like fuzzy one-inch caterpillars. They spin the silken webs and live communally, munching on leaf tissues within the web before dropping down to the ground to pupate in soil litter and emerge as moths in a few weeks. The adult moths mate and usually lay eggs on the underside of leaves which then hatch in the spring. Adult fall webworms are deceptively beautiful with snow white wings adorned with black spots. There are two races of the larvae: red-headed and bla…

Blame it on the Rain - Identification and Control of Powdery Mildew

For my first Southwest Yard and Garden column I’m answering the first  question I received as the new NMSU Extension Horticulture Specialist.

What is this white coating on the leaves of my chokecherry tree and what you would recommend to get rid of it?
                                                            -via Colfax County Ag Agent, Boe Lopez


The likely culprit for those symptoms at this time of year in New Mexico is powdery mildew.

Powdery mildew is a commonly occurring fungal disease across the country. Warm temperatures combined with high humidity in the plant canopy create the perfect conditions for the fungal spores to germinate and infection to spread. Therefore, the monsoon season provides ideal conditions for a powdery mildew outbreak in New Mexico.  I once noticed the symptoms on rose leaves and buds earlier in the summer, but it turned out a nearby sprinkler head was spraying too high, unnecessarily causing higher humidity in the bush.

Different species of…

Welcome to my DesertBlooms blog!

My name is Marisa Thompson and I am the Extension Horticulture Specialist for New Mexico State University.  

I'm based at the Los Lunas Agricultural Science Center, approximately 30 miles south of Albuquerque.
My position is divided between two departments at NMSU: 75% Extension (Extension Plant Sciences) and 25% Research (Plant & Environmental Sciences).
The mission of Extension Plant Sciences is to extend research-based knowledge and technology that will enable producers, clientele, and citizens to improve the quality of their lives and enhance the agricultural, economic, environmental, and social well-being of New Mexicans. The department of Plant & Environmental Sciences has a mission to provide academic instruction, research, and service that focuses on agronomic crop, fruit and nut tree, vegetable, and horticultural production as well as soil management in semiarid ecosystems.
Here are some of my responsibilities: 1) Develop an active Extension program in practical and su…