- Author: Chris M. Webb
This year’s landscape disease symposium will be held on Thurs., October 14 in Camarillo, at the Camarillo Ranch House. As always, there will be much to learn!
Scheduled topics include:
- Biology and control of Armillaria mellea – the oak root fungus
- Viral pathogens of ornamental plants
- Identifying common mushrooms in the landscape
- Biology and regulation of Asian Citrus Psyllid in California
- Scorch (Xylella) diseases in California
- Understanding citrus diseases in landscapes
- Exotic pest update
- New regulations affecting the landscape industry in Ventura County.
Details, registration instructions and contact information can be found here.
- Author: Chris M. Webb
Today, Maren Mochizuki shares with us preliminary findings from a local research project.
Soil pH along most of the California coast north of Los Angeles ranges between 7.3 and 8, which is generally higher than many edible and ornamental plants prefer. In some cases, availability of micronutrients such as iron is severely limited in soils above pH 8, leading to deficiency symptoms in plants. Other plants such as blueberries, rhododendrons, azaleas, and hydrangeas prefer acidic soil conditions (pH 6 and below).
To investigate potential soil pH reduction over time, UCCE Farm Advisors Jim Downer and Ben Faber and UCCE Staff Research Associate Maren Mochizuki applied coffee grounds, lemon waste, peat moss, pine needles, oak leaves, and municipal yardwaste in addition to elemental sulfur to soil with an unadultered pH of 7.8.
The project is on-going and is in its third year. Preliminary findings indicate that the combination of organic material plus elemental sulfur reduces pH to a greater degree and more quickly than either the amendment or sulfur alone. We have seen the greatest effect thus far with elemental sulfur plus coffee grounds, chipped lemon waste, or peat moss.
Lemon waste from Ventura County packinghouses.
Lemon waste was chipped before application and
incorporation into soil.
Coffee grounds (top) and peat moss applied
to soil prior to incorporation with a rototiller.
- Author: Chris M. Webb
Today is National Arbor Day. This special day encourages the care and planting of trees. A man by the name of J. Sterling Morton began the effort that led to Arbor Day in the 1850’s. Over the years his work and dedication led to the first national observance of Arbor Day in 1872. It is now celebrated nationally on the last Friday in April.
To learn more about the enthusiasm and community support of Mr. Morton’s ideas click here.
Suggestions on how to celebrate Arbor Day can be found here. It is important to note that state celebrations can differ from the national date. State Arbor Day celebrations are often observed to coincide with appropriate local planting times for trees.
Further information can be found on the Arbor Day Foundation website.
Information on tree selection, care and planting can be found on the UC ANR California Gardening – advice to grow by website.
- Author: Chris M. Webb
California’s oak trees are facing another challenge to their survival. The gold-spotted oak borer (GSOB) was identified in California in 2006; since that time, over 17,000 oaks have died from this pest.
The loss of oak trees, especially in the wild, brings many negative impacts: loss of wildlife habitat, greater risk of erosion and catastrophic fire, invasion of noxious weeds, as well as safety risks related to falling trees or branches.
The borer attacks the trunks and branches of mature oaks. While most pests attack trees that are stressed or weakened, the GSOB attacks large, healthy trees – including trees in yards. Thus far the damage has been contained to San Diego County.
Much work is being conducted in an effort to learn more about the GSOB. With more knowledge, researchers hope to be able to stop the destruction of these magnificent trees. At this time, all we can do is work together to slow the spread of the GSOB with the following steps:
- Do not transport oak firewood into or out of campgrounds or parks
- Chip infested oak wood to 1-inch pieces
- Cover stored oak firewood with 6 mm, UV-stabilized, durable plastic tarps in the spring. Secure all the edges of the tarp to the ground to prevent beetles from escaping
- Season oak firewood. Remove the bark and place the wood in direct sunlight
Pictures of the borer, the damage caused, and more information can be found here.
- Author: Chris M. Webb
This is the time of year for planting bare-root roses and pruning those already in the garden.
UC’s publication, “Roses in the Garden and Landscape: Cultural Practices & Weed Control", is a good source of information about rose care.
Topics include:
- Pests and other organisms
- Selection of plant varieties
- Cultural practices
- Planting site considerations
- Fertilizer and irrigation
- Pruning, including ways to influence bloom characteristics.
A related UC publication, “Roses in the Garden and Landscape: Insect and Mite Pests and Beneficials,” focuses on ways to use IPM (integrated pest management) and cultural practices to reduce pesticide use.
Austrian copper rose
Sweet Vivian
Vision