With frost in the forecast for Friday night, there have been questions about various frost protection methods in ginseng. We don’t have any specific research results for ginseng, but there has been work done for other crops. Here are the main methods used and advantages and disadvantages for their use on ginseng:
Row Covers/Frost Blankets
Row covers have proven to be the most effective for frost protection in low-growing crops, and are increasingly being used in ginseng. There are no studies in ginseng yet to determine the exact temperature difference between covered and uncovered gardens. However, in crops grown in open fields the protection ranges up to 6oC, depending on the thickness of the cover. The disadvantages of row covers are the added cost for materials and labour for application and removal, and that they interfere with fungicide applications. Because it takes time to apply the cover to the field, they have to be applied based on a forecast for frost conditions and forecasts can change over time. However, the protection they provide would probably be far better than any other existing method. Continue reading
With many new growers entering the lavender business, the Ontario Lavender Association (OLA) decided it is time to revisit the basics of lavender production. Lavender 101 will provide an overview of commercial lavender production from site preparation and planning through to oil distillation and bud cleaning. The workshop will be held in two locations to capture as many potential growers as possible. Note: Pre-registration and payment is required. See below for registration details. Continue reading
This year the Ginseng Scout Training will be held in the field for a more interactive experience. Anyone new to ginseng or scouting ginseng this summer is encouraged to attend. The training will include how to identify the major insect and disease pests of ginseng, pest biology and life cycles, sanitation and scouting protocols. Participants are encouraged to bring samples of suspected insect pests or diseases for identification.
Where: C&R Atkinson Farms Ltd., 228 Charlotteville Road 1, Forestville, ON (Just west of the hamlet of Forestville – approx. 20 minutes southwest of Simcoe). We will be travelling to a field site from there.
When: Thursday, June 4, 1:30 to 4:00 pm
Pre-registration is required. To register, contact the Agricultural Information Contact Centre at 1-877-424-1300 or by email at firstname.lastname@example.org.
Since we will be visiting a commercial ginseng farm, please practice good sanitation and ensure boots and clothing are clean if you have recently visited a ginseng field.
With a temperature of -0.8C recorded at Delhi on Thursday morning, there is some frost damage in some areas. With a lighter freeze occurring, damage is mostly restricted to edges of gardens and low pockets where cold air pooled. For those growers who haven’t seen this damage before, frost damage to seedlings causes stems to shrivel and the top to collapse onto the straw (Figure 1). Seedlings will not recover from this damage. Damage to older plants often weakens the stem causing the top to kink over (Figure 2). These plants often curl back up towards the light, but yield will be impacted. Symptoms do not always show up immediately. It can take a day or two for the damage to be evident.
Figure 1. Seedlings killed by frost.
Originally posted April 20, 2015
Hop Rhizome Sample Request for University of Guelph Research Project
A research project being conducted by the University of Guelph (U of G) is assessing rhizome samples from farm sites across the province to determine if downy mildew is present in hop rhizomes before symptoms of the disease can be observed.
The U of G research team is interested in hearing from Ontario hop growers who are establishing or expanding their hop yards this year and are willing to submit samples this spring for testing. The team is interested in examining rhizomes originating from within and outside of Ontario.
A total of 30-50 samples will be collected in 2015. Growers can submit up to 5 samples per farm (sample submission via post or courier is paid for by the grower) on a first-come basis.
The examination method is still being developed, therefore no results can be guaranteed at this time. However, if protocols are successful, results will be communicated to individual growers. If results are used in publications, growers’ identity will not be revealed for confidentiality.
If you are interested in submitting samples for testing, please email Amy Fang Shi (U of G) email@example.com or Evan Elford (OMAFRA) firstname.lastname@example.org for further instructions.
While many growers are accustomed to fumigating at this time of year with no need for supplementary water, 2015 is a bit unusual. The winter of 2015 was drier than normal for most of southern Ontario, with most regions experiencing less than 80% of average precipitation from January through March. Additionally, the very cold temperatures, sunshine and dry air means that much of the snow pack sublimated instead of melting into the ground. As a result, southwestern Ontario and eastern Ontario are currently listed as abnormally dry.
At the Simcoe Research Station, soil moisture measurements taken on a recently-prepared sandy loam field yesterday were at 15% of available water capacity, which is much lower than the levels stipulated on fumigant labels. For metam sodium-based fumigants (e.g. Busan and Vapam), moisture levels in the top 15 cm of soil must be between 60-80% of available water capacity immediately prior to fumigant application. For chloropicrin-based fumigants (e.g. Chloropicrin 100, Pic Plus), soil moisture at a 20 cm depth must be equal or greater than 50% available water capacity. Fumigation in most areas of southwestern Ontario at this time will likely require adjustments to soil moisture prior to application.
Soil moisture recommendations on fumigant labels are not new, however they are now one of the mandatory Good Agricultural Practices required on the new fumigant labels and both soil moisture and method of measurement must be included in your Fumigant Management Plan. While this is now a legal requirement, ensuring adequate soil moisture is also critical to the effective application of fumigants. If soil is not adequately moist at the time of application, the fumigant will move too quickly out of the soil. Since the efficacy of fumigants depends on the length of time the active ingredient is in contact with the target pest, you need to make sure the soil is sufficiently moist to keep the product in the soil. Furthermore, fumigant gas escaping from the soil prematurely can be a hazard, particularly when occurring in association with temperature inversions.
It is also important to note that one or two rainfalls may not be sufficient to bring soil moisture up to 50 or 60% available water capacity, particularly if the soil is very dry. Even if a heavy rain has occurred recently, check your soil moisture prior to fumigant application. For more information on monitoring soil moisture levels, refer to the OMAFRA factsheet Monitoring Soil Moisture to Improve Irrigation Decisions (http://www.omafra.gov.on.ca/english/engineer/facts/11-037.htm ) or view a new series of videos on the subject on the OMAFRA website. To find them, use Google to search for “irrigation OMAFRA”.
With the warm temperatures this week, older ginseng gardens are quickly emerging. A few seedlings are also beginning to emerge in the warmest areas. Ginseng at this stage of development is highly prone to all three foliar diseases: Alternaria, Botrytis and Phytophthora. Here is a reminder of what conditions favour the development of these three diseases:
Alternaria Leaf and Stem Blight:
Alternaria is favoured by mild temperatures and long dew periods. Rainy and humid weather is not necessary for Alternaria infection. A couple of long dew periods in a row are sufficient for Alternaria to infect the leaves or stems. The ginseng shade can extend the dew period, making it the ideal environment for Alternaria. Infection usually begins once the canopy begins to close, which reduces air flow around the plants and reduces drying. Alternaria can also be worse when the plant is stressed by another factor such as frost, dry conditions or wind damage. Continue reading