Leafhopper Monitoring and Blog - 2017
Overview
Welcome to the Leafhopper Blog!
The "Leafhopper Newsletter" is now the "Leafhopper Blog". This change was made in order to improve readability and allow for comments/feedback.
Like the Leafhopper Newsletter, these blog posts will summarize data from the regional leafhopper monitoring effort in Mendocino and Lake County.
Below you will find a list of all blog posts. The full blog can be found here: http://ucanr.edu/blogs/leafhopperblog/index.cfm
Regional Leafhopper Monitoring
Timing of practices to control the Virginia Creeper Leafhopper (Erythroneura ziczac Walsh) are not the same as those for the Western Grape Leafhopper (Erythroneura elegantula Osborn). This is primarily because VCLH adults begin to oviposit earlier in the growing season, which then leads to earlier appearance of nymphs and next generation adults in the vineyard.
Starting in 2015, UCCE initiated a regional leafhopper monitoring program that includes weekly announcements about population development, parasitism rates and the appearance of key life stages in the vineyard.
This regional monitoring not only provides useful information for growers, but allows UCCE to track the spread of VCLH populations and identify outbreak "hot spots".
Blog Posts
End of Season Leafhopper Parasitism Counts and Nymph Data
![Leafhopper Parasitism September 2018 Leafhopper Parasitism September 2018](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/56018small.jpg)
Nymphs In 2018, we conducted weekly nymph counts at three vineyard locations in Mendocino County from May 24- September 6. The first emergence of VCLH nymphs occurred during the week of May 14th (Table 1, Figure 1) and densities peaked on June 8, July...
Consult PCAs for Follow-up Applications for Leafhoppers - August 9th Update
![August 9 VCLH nymphs per leaf August 9 VCLH nymphs per leaf](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/54631small.jpg)
Monitoring efforts during the week of May 14th showed the first emergence of VCLH nymphs for the season (see Table 1/Figure 1 for # VCLH nymphs per leaf). The numbers of nymphs decreased on the week of June 11th as the three vineyards we are monitoring...
Consult PCAs for Follow-up Applications for Leafhoppers
![August 3 VCLH nymphs per leaf August 3 VCLH nymphs per leaf](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/54594small.jpg)
Monitoring efforts during the week of May 14th showed the first emergence of VCLH nymphs for the season (see Table 1/Figure 1 for # VCLH nymphs per leaf). The numbers of nymphs decreased on the week of June 11th as the three vineyards we are monitoring...
Overlapping Leafhopper Life-Stages
![July 19 VCLH nymphs per leaf July 19 VCLH nymphs per leaf](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/54208small.jpg)
Monitoring efforts during the week of May 14th showed the first emergence of VCLH nymphs for the season (see Table 1/Figure 1 for # VCLH nymphs per leaf). The numbers of nymphs decreased on the week of June 11th as the three vineyards we are monitoring...
Leafhopper Parasitism Update - July 2018
![Slide2 Slide2](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/54130small.png)
On July 9 we surveyed parasitism of Western grape leafhopper (WGLH) and Virginia creeper leafhopper (VCLH) across 9 sites in Mendocino and Lake counties (Fig. 1). WGLH parasitism was fairly consistent (average 38%), but there was little to no VCLH...
Second Generation Nymphs
![June 28 VCLH nymphs per leaf June 28 VCLH nymphs per leaf](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/53761small.jpg)
Virginia creeper leafhopper and Western grape leafhopper peak egg laying from the overwintering adults has passed (Fig. 1 & 2). Monitoring efforts during the week of May 14th showed the first emergence of VCLH nymphs for the season (see Table...
Adult leafhopper emergence has begun
![VCLH eggs per leaf 5 31 VCLH eggs per leaf 5 31](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/53498small.jpg)
Virginia creeper leafhopper and Western grape leafhopper peak egg laying from the overwintering adults has passed (Fig. 1 & 2). Monitoring efforts during the week of May 14th showed the first emergence of VCLH nymphs for the season (see Table 1 for #...
Critical time for monitoring leafhoppers in vineyards before adult emergence
![VCLH eggs per leaf 5 31 VCLH eggs per leaf 5 31](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/53148small.jpg)
Virginia creeper leafhopper and Western grape leafhopper peak egg laying has passed (Fig. 1 & 2). Monitoring efforts during the week of May 14th showed the first emergence of VCLH nymphs for the season (see Table 1 for # VCLH nymphs per leaf). On...
Critical time for monitoring leafhoppers in vineyards
![VCLH eggs per leaf 5 31 VCLH eggs per leaf 5 31](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/52988small.jpg)
Virginia creeper leafhopper and Western grape leafhopper continued laying eggs on basal leaves (see Fig. 1 & 2), although peak egg laying has passed. Monitoring efforts during the week of May 14th showed the first emergence of VCLH nymphs for the...
VCLH nymphs began to emerge on May 14th, 2018
![VCLH eggs per leaf 5 24 VCLH eggs per leaf 5 24](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/52787small.jpg)
VCLH nymphs began to emerge on May 14th, 2018 This season we will once again be monitoring the development of Virginia creeper leafhopper, VCLH, (Erythroneura ziczac) and Western grape leafhopper, WGLH, (Erythroneura elegantula) populations in Mendocino...
2018 Leafhopper Monitoring Update and Egg Deposition
This season we will once again be monitoring the development of Virginia creeper leafhopper, VCLH, (Erythroneura ziczac) and Western grape leafhopper, WGLH, (Erythroneura elegantula) populations in Mendocino County Chardonnay vineyards. The monitoring...
End of Regional Monitoring for 2017
![VCLH - Lake - Sept 6 VCLH - Lake - Sept 6](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/46579small.png)
We continue to see a mix of life-stages of both VCLH and WGLH at all of the regional monitoring sites (Figs. 1-2). As we move into the fall, adults will begin to enter reproductive diapause. These will be the leafhoppers that overwinter in your...
Overlapping Life-Stages Continue
![VCLH - Lake - Aug 30 VCLH - Lake - Aug 30](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/46420small.png)
All life-stages of both VCLH and WGLH are present in all vineyards (Figs. 1-2). Changes in densities of each life-stage over the past week varied across the sites.
Overlapping Life-Stages Continue
![VCLH - Lake - Aug 23 VCLH - Lake - Aug 23](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/46242small.png)
All life-stages of both VCLH and WGLH are present in all vineyards (Figs. 1-2). Adult densities appear to be increasing the most, although changes in densities of each life-stage over the past week varied across the sites. Two batches of A. daanei were...
Overlapping Life-Stages Continue
![VCLH - Lake - Aug 16 VCLH - Lake - Aug 16](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/46053small.png)
Adults, viable eggs and nymphs of both VCLH and WGLH are present in all vineyards (Figs. 1-2). Changes in the density of each life-stage over the past week varied across the sites. Another batch of A. daanei was released on Friday Aug. 18 in the Big...
Overlapping Life-Stages Continue
![VCLH - Lake - Aug 9 VCLH - Lake - Aug 9](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/45911small.png)
Adults, nymphs and viable eggs of both VCLH and WGLH are present in all vineyards (Figs. 1-2). Over the past week nymph densities appear to have increased the most relative to the other life-stages. Another batch of A. daanei was released last Friday...
Adults, Eggs and/or Nymphs Continue to Increase
![VCLH - Lake - Aug 2 VCLH - Lake - Aug 2](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/45806small.png)
Multiple, overlapping life-stages of both VCLH and WGLH are present at all sites and densities of adults, eggs and nymphs all continued to increase at most sites over the past week (Figs. 1-2). We are now seeing adult egg deposition higher up into the...
Second Brood Adults Continue to Increase
![VCLH - Lake - July 26 VCLH - Lake - July 26](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/45622small.png)
We continue to see increased adult densities of Virginia creeper leafhopper (VCLH) and Western grape leafhopper (WGLH) at most sites (Figs. 1-2). All life-stages (i.e. adults, eggs, nymphs) of both VCLH and WGLH are present in the vineyard now as these...
Second Brood Adults, Overlapping Life-Stages
![VCLH - Lake - July 19 VCLH - Lake - July 19](http://ucanr.edu/blogs/LeafhopperBlog//blogfiles/45450small.png)
We continue to see increased densities of second brood adults of both Virginia creeper leafhopper (VCLH) and Western grape leafhopper (WGLH) at most sites (Figs. 1-2). Nymphs and eggs are present at many sites as well and we will likely continue to see...
Tailgate Meeting - TOMORROW - Fri. July 21 - Hopland
Details: We'll be holding a "Tailgate Meeting" on Friday July 21 from 8-10am in Hopland. The plan is to provide updates and discuss the UCCE Area Wide IPM Program for Virginia Creeper Leafhopper. This meeting has been approved for 2.0 CE units of...