UCCE Ventura County- Blogs

IPM for Landscapers

The University of California Statewide IPM Program presents the UC IPM Green Bulletin. This newsletter focuses on specific practices and information that landscape and structural pest management professionals can incorporate into their daily work to manage pests effectively while reducing pesticide runoff and other environmental problems.

If you have a question you would like to see answered in a future issue, send it to ucipm-community@ucanr.edu.

Sign up to receive this newsletter electronically.

ground squirrel

California HLB Quarantine Area Expanded

Agricultural officials recently expanded the areas in California quarantined for citrus greening disease [also known as huanglongbing (HLB)], which is spread by Asian citrus psyllids. The quarantined area in Orange and Riverside counties was increased by a total of approximately 31 square miles. The U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA APHIS) in cooperation with the California Department of Food and Agriculture (CDFA) took this action.

The quarantine expansions were made because of citrus greening detections in plant tissue samples collected from residential properties in Orange and Riverside counties. There are approximately 3 acres of commercial citrus in Riverside County impacted by this expansion.

USDA APHIS is applying safeguarding measures on the interstate movement of regulated articles from the quarantined areas in California. These measures parallel the intrastate quarantines that CDFA established on Oct. 22. This action is necessary to prevent the spread of citrus greening to non?infested areas of the United States.

The specific changes to the quarantined areas in California can be found on the APHIS Citrus Greening and Asian Citrus Psyllid website. USDA APHIS will publish a notice of this change in the Federal Register.

Additional information may be obtained from USDA APHIS National Policy Manager Abby R. Stilwell (abby.r.stilwell@usda.gov or 919-323?6296), or from Assistant National Policy Manager Daniel Murphy (daniel.m.murphy@usda.gov or 775-221-9237).

Learn about other HLB quarantine expansions in California earlier this year.

HLB symptoms

Fire Effects on Soil

Fires are common and we usually just think of the effects it has on plants and structures, but what impact can it have on soil. I recently came across a guide book from the US Forest Service that addresses how to evaluate fire impact on soil. Following wildfires in the United States, the U.S. Department of Agriculture and U.S. Department of the Interior mobilize Burned Area Emergency Response (BAER) teams to assess immediate post-fire watershed conditions. BAER teams must determine threats from flooding, soil erosion, and instability. Developing a postfire soil burn severity map is an important first step in the rapid assessment process. It enables BAER teams to prioritize field reviews and locate burned areas that may pose a risk to critical values within or downstream of the burned area. By helping to identify indicators of soil conditions that differentiate soil burn severity classes, this field guide will help BAER teams to consistently interpret, field validate, and map soil burn severity.

The guide is here:

https://www.fs.usda.gov/rm/pubs/rmrs_gtr243.pdf

 

field guide to soil burn

Medfly Quarantine Area Expanded

The U.S. Department of Agriculture Animal and Plant Health Inspection Service (USDA/APHIS) and the California Department of Food and Agriculture (CDFA) expanded the Mediterranean fruit fly (Medfly) quarantine in Alameda and Santa Clara counties in California twice in October.

The expansions are in response to the confirmed detections between Oct. 7 and Oct. 15 of 22 wild female Medflies, 14 of them mated, and 12 wild male Medflies from traps in trees in residential areas.

USDA APHIS and CDFA established the quarantine on Sept. 6, following the detection of a mated wild female Medfly in the city of Fremont in Alameda County on Aug. 28. That Medfly came from a trap in an orange tree in a residential area. The agencies expanded the quarantine on Sept. 11, following the detections of additional flies.

As a result of the latest detections, this quarantine area increased by 38 square miles to 121 square miles. There are 54 acres of commercial agriculture in the quarantine area.

USDA APHIS is applying safeguarding measures and restrictions on the interstate movement of regulated articles to prevent the spread of Medfly to non-infested areas of the United States, as well as to prevent the entry of these fruit flies into foreign trade. USDA APHIS is working with CDFA and the agricultural commissioners of Alameda and Santa Clara counties to respond to these detections following program guidelines for survey, treatment and regulatory actions.

The APHIS exotic fruit flies website contains a description of the new quarantine area, as well as all current federal fruit fly quarantine areas. USDA APHIS will publish a notice of these changes in the Federal Register.

Additional information on the Medfly quarantine is available from USDA APHIS National Policy Manager Richard Johnson at  richard.n.johnson@usda.gov or by phone at 301-851-2109.

Medfly-alone

Art of the USDA

The USDA Pomological Watercolor Collection is one of the most unique collections in the Rare and Special Collections of the National Agricultural Library (NAL). As a historic botanical resource, it documents new fruit and nut varieties, and specimens introduced by USDA plant explorers from the late 19th and early 20th centuries.

The collection spans the years 1886 to 1942. The majority of the paintings were created between 1894 and 1916. The plant specimens represented by these artworks originated in 29 countries and 51 states and territories in the U.S. There are 7,497 watercolor paintings, 87 line drawings, and 79 wax models created by approximately 21 artists.

Lithographs of the watercolor paintings were created to illustrate USDA bulletins, yearbooks, and other publications distributed to growers and gardeners across America.

Today, the collection is preserved in NAL's Rare and Special Collections, where it serves as an important research tool for a variety of users, including horticulturists, historians, artists, and publishers. In 2010 and 2011, the entire printed collection was digitized to improve public access to this valuable resource, and to better preserve the paintings by reducing the need for researchers to handle them. Today, the whole collections is searchable.

In 1886, the United States Department of Agriculture (USDA) established the Division of Pomology to oversee the collection and distribution of new varieties of fruits, and to disseminate information to fruit growers and breeders. USDA commissioned artists to create technically accurate illustrations of newly introduced cultivars for the division's publications. In 1887, William H. Prestele was appointed as the first artist for the Division of Pomology. Henry E. Van Deman, division chief, explained the importance of Prestele's appointment in his 1887 Report of the Pomologist:

Up to August 1, when Mr. Prestele took his place here, there was no one to make drawings of fruits which were being daily received for study and comparison...but since then a part of the drawings have been made in India ink, and others have been reproduced in water-colors, all in the most skillful manner, showing the natural size, shape, and color of both exterior and interior of the fruit, with the leaves and twigs characteristic of each. These are invaluable for comparison and reference, and a portion for publication.

Over the years, other artists were also assigned to the division and their watercolors were used for lithographic reproductions in USDA publications and as scientific documentation of research results. Although some of the watercolor paintings are not signed, we know of 21 artists (nine of whom were women) who contributed to this important resource.

A more detailed history of the USDA fruit pictures is found in Paula Sewell's Garden History Girl blog:

https://www.gardenhistorygirl.co.uk/post/the-fruits-of-america-part-1-the-us-department-of-agriculture-s-pomological-watercolor-collection

 Annona cherimola

 

 

Read more