Non-Emerald Ash Borer Ash Problems

    Emerald ash borer (EAB) is eventually going to come and kick some major ash in Pulaski County KY.  However, even without this pest, ashes have their share of problems.  Let's go over a few of the most common.
     Ash/lilac borer -- unlike EAB, these borers tend to infest already stressed ash trees.  Symptoms include tree decline (thinning canopy) and round exit holes.  Pictured here is a pupal case that is often observed on the bark of ash trees.  All borers are hard on trees and will cause thinning of the canopy and general decline.
     Ash anthracnose -- this fungal disease usually hits in cool, moist springs. Brown spots develop on the leaves, leaves will usually fall off, but the tree will regrow a new set of leaves.  This is not good for the tree as it has to have double the energy supply to create a whole new set of leaves. You may see general dieback of the canopy if the tree is infected multiple seasons.

     General decline -- this omnipresent problem is hard for many tree owners to understand. As much as we like to think trees live forever, they don't. Drought, floods, improper pruning, planting too deeply, changing the grade, and trenching near a tree can all cause the tree to be unthrifty and be the start of a downward spiral.



     

Redundant Rose Rosette

    Knockout Roses have been all the rage for the last few years.  Even as a non-rose person, I have been impressed.   No black spot (or very little) and pruning?  Prune whenever you feel like it!  The plants will live and bloom and bloom and live!

     However, like all good things, they must come to an end.  Case in point:  Several calls and many rose specimens in the disease diagnostic lab with weird, red, thorny growth. 

     All the Knockouts here at our office were removed due to this problem, a disease problem.  You might say ‘How?  Knockouts are disease resistant!’. 

     Nope, sorry, they are not resistant to rose rosette.  

     Symptoms. This lethal disease affects all weedy and cultivated roses. Earliest symptoms include increased growth of shoots with red coloration and distortion and dwarfing of leaves (Figure 1). Affected shoots appear to be more succulent than normal and they develop a proliferation of thorns (Figure 2). This abnormal overabundance of thorns is a useful field symptom for diagnosis, because the new shoots of many roses are naturally reddish colored. Diseased shoots are not winter-hardy and will produce few blooms or flowers may be deformed. Infected plants produce fewer roots than normal. The disease progresses to the rest of the plant until all the new growth is affected and the plant declines or is killed in winter. Roses may succumb in just one season, or symptoms may continue for another season or two.

     The cause of rose rosette disease was thought to be a virus, but recent research suggests that a phytoplasma infection is responsible for the symptoms. In nature, it is spread by a tiny eriophyid mite.

     Disease management. Infected plants must be removed and destroyed so that the pathogen is not spread to healthy plants nearby. Care must be taken to avoid scattering disease-carrying mites to the other plants. Early detection is essential. Rose rosette disease is normally systemic in the plant, but at the first indication of infection on a shoot, it might help to clip off the affected shoot in hopes that the rest of the plant is still unaffected. Multiflora rose could be a reservoir for the disease so they should be removed from the neighborhood of cultivated roses.

 

 

Knockout Roses -- Yes They Can Have Problems!

Here at the Pulaski Co Extension office we have about 5 pink single Knockout roses and 5 double Knockouts planted. Last year I saw this problem and stupidly did not remove the plants. This year, the problem is here again!




This is called rose rosette virus. It is incurable and terminal. It's best to remove affected plants to protect others from getting the virus. It is transferred via mites.

Sorry plants, but y'all are outta our garden!

Bagging Apples

Ever heard of this? Apple bagging is simply placing individual apples inside bags while they are still on the tree. Bags are put on when fruit is about quarter-sized. Bags remain on til about 3 weeks before harvest. Bagged apples will not color up properly, so taking them off well before harvest is a must.

Why, why, oh why would anyone do this? Well, apples get plenty of disease and insect pests. Most backyard fruit growers do not want to apply lots of pesticides. So....by bagging fruit we are physically keeping the pest off the fruit without having to spray. An organic pest control method.

In addition to using the Japanese apple bags (from the website above), a UK entomologist gave me some nylons. Yes, there is anecdotal evidence that nylons (like what women slip on when trying on shoes) can work to deter pests.

I grow Liberty apple which is very disease resistant, but no apples are insect resistant. Here are my photos of bagged, nyloned, and not-bagged apples.



Pretty cool. But let me tell you, putting bags on apples is dang time consuming, especially the Japanese apple bags. Most of the bags I had put on had fallen off mid-season. The nylons were much easier to put on and did not tend to come off with bad storms and weathering.

The bagged apple was the biggest of the 3, shown below. And you can see what covered each of the 2 bagged apples.

Late blight hits...in a personal way

Late blight of tomatoes has hit home. Literally. A half-acre of my husband's tomatoes that were intended for fall sales has succumbed to this aggressive disease. The weather has not been helpful at all in reigning this monster in, either. Fog, rain (or even just a spritz of rain) and cooler weather have all contributed.

Here are some pictures -- and it ain't pretty.






Late blight is in Pulaski Co. FYI.

We Know Early Blight, but Late Blight??

Yes, late blight, the potato famine, a disease we rarely EVER see in Kentucky is here. And with a vengeance, especially in Eastern KY. This disease attacks both potatoes and tomatoes and has been diagnosed on tomatoes in Kentucky in the following counties: Laurel, Larue, Jackson, Breathitt, Johnson, Montgomery, and Wolfe.

Late blight is a fast-moving disease that has very much enjoyed the cool, damp, cloudy weather that we've had pretty much all this summer.

We are highly encouraging gardeners to scout their tomatoes (and potatoes) for this disease. Fungicides are recommended -- something like chlorothalonil (Daconil, Fungonil) or mancozeb/maneb.

For those of you doing things organically, use fixed copper or Oxidate. Under high disease pressure, even these will not work.

Let me know if you see anything suspicious in your gardens!