The Different Phases of Fireblight Since fireblight is a bacterial disease that has 4 different entries into the apple tree, I wanted to review how to control the disease. It has to be approached before it sets in or it can kill your trees. There is a reason why they call it "Fireblight". It can move like wildfire and under optimal conditions, it can destroy an entire orchard in a single growing season. And you don't play with fire! That's why I always tell all home growers to spray copper at silver tip and strep at bloom. Those are two sprays that I would never bypass. I've seen what firebl ..read more

An Apple a Day Is Good for You (In So Many Ways It's Hard to Keep Count) Eat an apple a day. Doing that could help you remember to eat an apple a day. It might also help keep your skin from wrinkling. And apple consumption appears to promote hair growth. In addition, scientific research continues to build more and more evidence that antioxidants in apples are protective against cardiovascular disease and cancer development. Apples just make sense as a daily part of the human diet. Our forebears instinctively came to that same conclusion and adopted the maxim, "An apple a day keeps the d ..read more

Seaweed Digests for Critical Spring Temperatures for Frost or Freeze Damage Given the weather patterns we have experienced so far this late winter and early spring, a spring frost seems very possible. Once the fruit has set, then the critical temperatures that can damage the fruit become lower. We will need to constantly assess the stage of development our trees are at over the next weeks and their susceptibility to possible freeze injury.   If we continue in a spell of colder weather, apple trees will continue to develop more slowly, but once they begin showing tight cluster, pink and ..read more

Simplified Pruning and Training Plan for the Tall Spindle System Spreading the scaffolds on young fruit trees can aid in bringing about improved tree form, earlier fruit production, and improved fruit quality. Branches growing in an upright position tend to be vegetative and unfruitful for a longer period of time than those growing in a more horizontal position. The reason for this is related to the natural growth regulators in the tree. Thus, spreading the scaffolds of a young fruit tree to a pendant position below horizontal favors initiation of spur growth and flowers. First Leaf - Firs ..read more

When Apples Will Freeze on the Tree Apple fruit will withstand up to 4 hours at 28°F before serious injury occurs, but it is difficult to give a hard and fast rule to predict injury based upon minimum temperatures and duration, as the recovery depends not only on the extent of freezing, but also the rate of thawing. The fruit tissues of apples have sugar and other constituents that lower the freezing point of fruit below 32°F. The freezing point of fruit varies between varieties and fruit maturity (probably due to differences in sugar content); even so, apples begin to freeze at 28.5 to 2 ..read more

Apple Maggot Arrival Time It's time to set apple magott (AM) traps in your trees or orchard if you have not done so already. I usually do this around July 4, but with the extreme heat and drought we have experienced, I delayed a few days. We are at about 1290 DD from January 1 as of today, and I trapped our first fly July8, so if you have not done so, it is time to get out the apple maggot traps and get them set.  As always, be sure to follow all label directions on the bottle for proper application.    For additional information, see the following fact sheets and guides whi ..read more

Fighting Japanese Beetle Japanese Beetle emergence has begun here in Northern Illinois, and beetles have been spotted in other locations of the Midwest and elsewhere by home growers. Once Japanese Beetle have emerged in one location, it is only a matter of time before it emerges in another. They tend to gravitate to Honeycrisp trees first (Figure 1). Due to the large amount of carbohydrates produced by the Honeycrisp trees, which is what makes the variety so sweet, the Japanese Beetle is seemingly attracted to it just like we are! Honeycrisp seem to be the first leaves that attract them and ..read more

Peak Egg Hatch for Codling Moth is Upon Us  To determine when flight begins for codling moth, commercial growers make use of pheromone traps. Once moths have been trapped for two consecutive days in a row, a biofix is set that initiates the beginning of growing-degree-day calculations. We know that at approximately 100 degree days after the biofix date codling moths begin to lay eggs and those eggs begin to hatch at approximately 250 degree days after biofix. And peak egg hatch is approximately 500 to 650 degree days (DD) after biofix.  It is this information that aids in the timing o ..read more

Preparing for Plum Curculio With apple scab season in our midst, and petal fall coming to an end, it is time to turn our attention to several insect pests. Plum curculio (PC) is one of the most difficult insect pests to contain. They enter the orchard from the perimeter after the adults pass the winter hidden under leaves, along fence rows, in brush piles, rock walls and in other protected places. In spring when the weather warms up at night (mean temperature 60°F. or maximum temperature above 75°F.), about the same time apple trees are blooming, the adults become active. The adult plum curc ..read more

A Word (or Two) About Fungicides Fungicides can be either contact fungicides or penetrant fungicides and non-systemic, locally systemic or fully systemic. Mobility describes fungicide movement after it is applied to a plant. To understand differences in mobility, it’s important to know the difference between absorption and adsorption.  It is also important to know a little about the plants vascular system.  A plants vascular system is made up of phloem and xylem.  These are complex tissues that perform transportation of food and water in a plant. They are the vascular tissues ..read more