- Author: Elizabeth J Fichtner
Those allergic to olive pollen are well aware that olive bloom in Tulare County is usually expected in mid-May. This year, however, the bloom arrived by mid-late April during a cool period in the southern San Joaquin Valley. The coordination of bloom with cooler temperatures is fortuitous for local table olive growers producing the ‘Manzanillo' olive for the black ripe industry. High temperatures at bloom limit fruit set of ‘Manzanillo' because the andromonoecious trees (aka: hermaphroditic) lack self-compatibility in the heat. Under optimal weather conditions at bloom, ‘Manzanillo' is self-compatible, meaning that the pollen from a perfect flower may be transferred to the pistil of the same variety (or even the same flower) for fertilization. When warm temperatures occur at bloom (ie. temperatures exceeding 87◦F at bloom), ‘Manzanillo' pollen develops slowly resulting in reduced or no fertility. Growers mitigate the risk of heat at bloom by planting a compatible pollinator cultivar (ie. ‘Sevillano) within ‘Manzanillo' orchards, or by applying compatible pollen to solid blocks of ‘Manzanillo.'
On April 21, 2016, the olive block at Lindcove Research and Extension Center was approaching full bloom.
- Author: Elizabeth J Fichtner
Kurt Schmidt, Lindcove Research and Extension Center (LREC) Superintendent and Elizabeth Fichtner, Farm Advisor, UCCE Tulare County, video-conferenced with the second grade classes of Mrs. Stella Guiry and Mrs. Jennifer Solano at Stewart School in Garden City, New York. The outreach program was organized by Ms. Dawn Ripp, the Stewart School librarian. Using remote conferencing technology, Elizabeth presented a powerpoint presentation to the students, highlighting the importance of science and technology for agricultural productivity, economic and environmental sustainability, and the maintenance of a healthy and safe food supply. Students then addressed Kurt Schmidt with questions regarding his experiences as a citrus grower, from protecting trees from the cold to production of seedless varieties. The outreach program was timed in conjunction with students planting a school garden and making mini-greenhouses out of recycled materials.
Kurt Schmidt and Elizabeth Fichtner answer questions posed by elementary school students at Stewart School in Garden City, NY.
Students congregated in the school library video conference with Elizabeth Fichtner.
- Author: Elizabeth J Fichtner
Tulare County has a new walnut rootstock observation block containing rootstocks recently generated by the Walnut Improvement Program (WIP) at UC Davis. The last rootstock observation block in the southern San Joaquin Valley was planted in 2007 and does not contain the newest experimental genotypes that have emerged from the WIP.
The new observation block was planted at the Lindcove Research and Extension Center on April 11, 2016 and contains four experimental rootstocks and 4 commercial rootstocks including VX211, Vlach, RX1, and seedling Paradox. All rootstocks were June-budded to the ‘Chandler' variety. The Tulare block is only one of six walnut rootstock trials established throughout the walnut growing regions of California. The project is supported by an SCRI (Specialty Crops Research Initiative) grant and by the Walnut Board of California.
Caliper diameter was measured below the graft union after planting.
Rootstock genotypes were planted in a randomized complete
block design with five trees per plot.
- Author: Elizabeth J Fichtner
April 4, 2016
A groundwater recharge study was initiated in an almond block in the southern San Joaquin Valley in February 2016. Funded by the Almond Board of California, the goal of the study is to determine whether surface water applications will successfully recharge aquifers without adverse effect on orchard health and productivity. Biweekly stem water potential measurements are made by our local UCCE Tulare County nut extension program researchers and staff. Our grower cooperator is hoping for a surface water allocation in May 2016 in order to impose the appropriate irrigation treatments on the block.
Elizabeth Fichtner, UCCE Farm Advisor, bags shoots for midday stem water potential measurements during bloom.
Sabrine Dhaouadi, UCCE Junior Specialist, uses the pressure chamber to measure stem water potential.
- Author: Elizabeth J Fichtner
Lethal Paradox Canker sampling begins again in Tulare County
Early symptoms of LPC may include small bleeds on the rootstock and a general canopy decline, but the canker may eventually envelope the rootstock, girdling the tree and causing mortality. In Tulare County, the most recent reports of LPC have been in ‘Tulare' and ‘Chandler' blocks, and generally in orchards ranging from approximately 10-15 years old. Disease incidence has reached approximately 6% in some affected orchards but is typically less than 1%. Because the disease is observed in mature orchards, shade from neighboring trees can complicate replacement of LPC-affected trees. Also, although trees used to replace LPC-affected trees have not been observed to express the disease, the replacement trees are subject to disease caused by replant pests such as plant parasitic nematodes.
Photo Caption: Dr. Greg Browne samples a Tulare County walnut orchard for lethal paradox canker.
Lethal Paradox Canker 3-15-16