- Author: Annemiek Schilder
In this blog series, Dr. Annemiek Schilder, Director, UCCE Ventura County and Hansen Agricultural Research and Extension Center, shares her observations about the natural world across the seasons. As she says:
"Gently observing your surroundings with curiosity will teach you some amazing things. There are so many fascinating things happening under our noses, only wanting for an observant eye."
The other day I spotted a gorgeous red dragonfly in my garden. He – yes, it was a male - cocked his head towards me several times and studied me with his big compound eyes as I inched closer to take a picture. He waited patiently while I tried to get him into focus, then eventually flew off. The flame skimmer dragonfly (Libellula saturata) is common in California and the Western US. Males have an orange-red body with orange sections on the wings, whereas the female is paler with an amber tinge along the upper edge of the wings.
Dragonflies speak to the imagination with their bright colors, transparent lacy wings and aerial acrobatics, inspiring poets and artists through the ages. They are often seen as a good omen and a source of comfort during times of loss. In Japan, the dragonfly is a symbol of strength, courage, and happiness whereas to Native Americans, dragonflies signify change, transformation and healing.
Dragonflies belong to the insect order Odonata, which means “toothed”, for their serrated mandibles − entomology-speak for jaws with teeth-like projections. Adult dragonflies feed on soft-bodied insects such as mosquitoes, flies, moths, butterflies, and flying ants, ambushing them in mid-flight. They have almost 360-degree vision due to their huge compound eyes and can see many more colors than humans can. Dragonflies are amazing flyers, achieving speeds over 30 miles per hour, and are able to fly forwards, backwards and remain stationary with the help of flight muscles that control each of the four wings separately.
The flame skimmer dragonfly is mostly found near warm ponds or slow-flowing streams. In colder regions they are a common sight around hot springs. The larvae, also called nymphs or naiads, spend 2 or more years living in shallow water where they feed on mosquito larvae and other aquatic insects, small fish and tadpoles. In order to grow, they have to molt (shed their skin) multiple times. Adult dragonflies emerge in the spring and live for about 6 months during which time they have to find a mate. As I was observing two flame skimmers chasing each other, I was reminded that dragonflies can be fiercely territorial. After mating, the female lays her eggs by dipping her abdomen repeatedly in the water while hovering above the surface.
Watch the life cycle of dragonflies in this National Geographic video.
Related Reading:
Fireworks in the Garden: Octopus Agave
Photo by Sensei Minimal on Unsplash
- Author: Cris L. Johnson
The event includes other agricultural professionals and UC experts that will provide updates on pests, research and compliance issues.
Date: Tuesday, December 3, 2013
Time: 9:00 am to 4:00 pm
Location:
Los Angeles County Arboetum and Botanic Garden
301 N. Baldwin Ave.
Arcadia, CA 91007
Registration at the door.
Contact: Jim Downer, 805-645-1458
Learn more about the Entomological Association of Southern California here.
Meeting Agenda
- Author: Cris L. Johnson
Once a tree has been infected by the psyllid that carries and transfers the huanglongbing (HLB) bacteria to the tree there has been no alternative but to quarantine the infected area and destroy the tree. To complicate the issue further, the disease can lie dormant and be difficult to detect as the infection spreads from tree to tree.
Efforts to control the psyllid through pesticides have been ineffective and while quarantines have helped raise awareness and slowed some of the spread, a viable weapon to combat this invasive pest has been unavailable until recently.
Mark Hoddle, director at the Center for Invasive Species Research at UC Riverside, has been experimenting with a tiny parasitic wasp, Tamarixia radiata, that feeds on and kills the psyllid. After a series of tightly controlled and successful tests, the wasps have been released on infected sites and have been effective in reducing the psyllid population. There is no danger to pets or humans and the release program has been approved by the Department of Agriculture.
To learn more about this effort, please see the UC Riverside Newsroom article.
- Author: Cris L. Johnson
The website explores chemical injury, nutritional disorders, physical and physiological disorders found in the field and during research. The team collaborates and shares information about these issues and discuss methods for dealing with them.
The website is presented in English and in Spanish and is accompanied by large photos that focus on the problem areas.
Check out the new website: Strawberry Disorders: Identification and Management.
- Author: Cris L. Johnson
Spider mites are a major recurring pest of strawberry. If left untreated, these pests will infest fields, decrease yield and eventually kill your plants. Several methods are available to help control spider mites on strawberry including biological control (i.e., predatory mites) and miticides. Watch this video to learn more about spider mites in strawberry and their control:
