Several days ago, we noticed that fruit and leaf drop are beginning again. From what I can gather, this might be some of the first of the season, at least in our area in Central Florida. This is the same sort of drop we’ve seen the past couple of years at about this same time. It’s hard to pin down a cause, but it seems the fruits and leaves most affected by this drop are affected with greening symptoms. Here’s a quick drive through video of several trees to give you a general idea what we’re seeing in the groves. The video is after the jump.
• Aperture:ƒ/1.8• Credit:Steven Rogers• Camera:DMC-LX7• Taken:October 1, 2014• Copyright:© 2014 Steven Rogers Photography All Rights Reserved• Focal length:4.7mm• ISO:80• Shutter speed:1/125s• Title:Lake Hancock Fruit Drop
Checking the groves for insect damage today, I see something I haven’t seen for several years. There’s a pest of citrus, called rust mites, that causes a brownish injury on the rind of the fruit. Normally, we’d start treating for this insect this week, but a very heavy rain yesterday literally washed the insect off the fruit. We got close to 4 inches of rain, and this will buy us 7 to 10 days before having to treat for this insect.
Tonight, we’re having heavy rain storms. Conditions are flooding some areas in the groves, but overall, this will be good for the trees. Although we are past the time of year when diseases like canker are spread to most susceptible fruit, black spot is still a concern.
Update: We had up to 4 inches in some groves between Lakeland and Bartow.
Postbloom fruit drop disease, a major cause of early-season crop losses in citrus, hit hard in Central Florida groves this year. This was unexpected, since the disease severity was nowhere near as high last year. This means that future years will need timely intervention to prevent the disease from recurring or becoming much worse.
• Aperture:ƒ/2.4• Camera:iPhone 5• Taken:July 6, 2014• Focal length:4.12mm• ISO:50• Location:27° 52′ 38.47″ N 81° 45′ 47.79″ W• Shutter speed:1/146s
We are getting a lot of rain this time of year in our Florida citrus groves. The good thing is that it’s helping the trees combat some diseases, such as greening. Most trees, including many sick ones, respond well to the abundant rain and ground and foliar fertilizers that are being applied to the trees. This reinforces my belief that abundant water is more important to helping citrus trees survive greening than initially thought. Others are coming around to this point of view, as shown by some new research that has been initiated to look into those questions. However, the abundant rain makes other diseases, such as citrus canker, worse in some cases. As you can see in this photo, we have a very large citrus canker lesion in an early-variety orange block. This lesion is over 2 inches high and 1 inch wide. Clearly, we have to be diligent about controlling diseases that reach these levels, because otherwise the crop is difficult to sell.
Despite the pressures of citrus greening, the crop yield so far looks good in some Florida citrus groves. This tree is about 4 years old. I’ve highlighted each of the fruits in about a 1-square meter area in the canopy to show you the numbers of fruits we’re seeing in these trees. Currently, these fruits are 2- to 3-inches in diameter, suggesting that they might size up well if they can hold onto the tree until they mature. More
• Aperture:ƒ/2.7• Credit:Steve Rogers• Camera:Oregon 650• Taken:August 13, 2013• Focal length:4.0819997809mm• Location:27° 55.9357′ 0″ N 81° 54.1551′ 0″ W
The fruit drop in the Florida citrus industry has been big news lately, such as talked about in this article in the Lakeland Ledger and this one in Fresh Plaza. There are a lot of possible contributing factors to this drop and it’s generally thought that greening is the biggest culprit. But, another reason can be what we call “overbearing”, which is where trees simply set more fruit than the physiology of the tree is able to support. This photo shows an example of a heavy fruit set in a Florida orange grove resulting from the recent bloom this season. It’s not likely all such fruit will hang on the tree until maturity.