Blue Diamond Almond Facts January-February 2023



Welcome to 2023! It’s hard to believe that 2022 is now in the past, and we are gearing up for a new and exciting year of almond farming. Before we know it, buds will push, blooms will open, and the proverbial saying of “there is no going back now” will be said by every grower throughout Blue Diamond’s nine districts. Since it’s getting close to bloom time most publications will talk about bloom time diseases like Brown Rot, Jacket Rot, and Shot Hole. I will talk about these briefly in this article, but since they will be discussed in other publications and meetings, I thought I would focus on the exciting topic of…budgets! I’m guessing I may have lost a few readers with that sentence because budgets are not exciting. They may seem daunting, but they are absolutely necessary for a successful operation.

Before we get to the budget let’s talk about spring diseases in almonds. In order to control the following diseases, you must be aware of the weather forecast. I know when I worked as a PCA, I always said during bloom time I also became a weatherman. Being prepared for a weather event is critical to the success of a fungicide application. The first spring disease that usually pops into people’s minds is brown rot. In an article written by Mitch Lies, where he interviews Jim Adaskaveg, a UC Riverside Professor and Plant Pathologist, Adaskaveg said brown rot “is the most prominent disease at bloom.” The disease does need moisture, but not much. Brown Rot can be present with little to no rain because there is moisture present in the flower itself. The next disease that I’ve seen become a little more prevalent in my area is jacket rot/green fruit rot. This disease, like many others, must have the right conditions to be present. Jacket rot usually appears later in bloom when the fungus effects the dropping petals, jackets, or other flower parts and because of the moisture they stick to the young almonds or leaves. It is most prominent in dense clusters of almonds because the falling plant material gets trapped in the cluster and can lead to the infection of the whole cluster. Shot hole is another common springtime disease but has become less of an issue over the years. It is usually easy to discover as it develops small reddish spots on the leaves, and typically has a dark spot in the center. These lesions can show up on other parts of the plant, but most people

discover it on the leaves. Jim Adaskaveg says shot hole “hasn’t been much of an issue over the past decade or longer, however, in large part, because fungicides used to control other diseases have kept it at bay.” The last bloom time disease I would like to shine light on is anthracnose. Like the other diseases, anthracnose is dependent on environmental conditions. Heavy moisture/rain along with warmer temperatures will lead to the development of the disease. Symptoms appear as blossom blight, fruit infections, and spur and limb dieback. Anthracnose is not a disease you want to get a foot hold in your orchard. It can have a multiple year effect because of the infection to spurs and limbs. Growers may have to prune out the infection, in combination with a strong fungicide program to eradicate it. The diseases that cause growers so many headaches at bloom have been identified, but how do we control them ? There are quite a few fungicides that growers can pick from. The main thing to keep in mind is to pick the correct fungicide for the disease you are trying to prevent and the correct timing of when to apply the fungicide. In Figure 1 you will see a chart of different diseases and time of an application. The chart is on a 0-3 scale with 0 being ineffective and 3 being most effective. This can help you target past disease issues. For example, a grower has had a history of high jacket rot infection, that grower can look at this chart and know they need protection at the full bloom timing.



Made with FlippingBook - Online Brochure Maker