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Inspection Report Week of March 12, 2018

At a pest workshop in Mobile last fall, Dr. Kassie Conner from the Auburn Plant Lab spoke about tip blight on arborvitae, cryptomeria, and junipers caused by phomopsis and kabatina disease organisms.  These diseases are devastating to young plants while plants more than five years old are less seriously damaged.  Here's a really good write-up from Alabama Extension about these diseases published in 2004:   A list near the bottom details resistant and susceptible varieties.

Kassie said that the pathogens infect through wounds caused by insects or mechanical damage.  A possible insect suspect might be the juniper paria.  I find these on many junipers and 'Black Dragon' cryptomeria where tiny bites have been taken out of the tips of foliage.  I have records of trapping them in late February and early June.  I have never put the two together until Kassie mentioned it.  This might be a situation to keep an eye on.  Kassie suggested spraying for the beetle if they were found in significant numbers.

The beetles can be monitored by tapping foliage over a white surface.  My white Frisbee works best for this because beetles often fold their legs in and drop when disturbed.  The edges of the disc help capture the beetles and hold them where they can be observed.

Kassie said that the timing for control differs.  For phomopsis, begin in early spring and continue at 10-14 day intervals.  For kabatina, fungicide applications should begin in the fall.

The brown tips are in themselves not bad or very noticeable.  They are just dried up feeding sites where beetles have taken out the growing tip.  However, these can be wound sites for pathogens to enter on susceptible varieties.

Maskell scale can be a serious problem on ‘Blue Point’ juniper.  This scale is extremely small. It sometimes looks like the plant has mites.  Often a hand lens is needed to see it.  An extension article from Maryland says: “The exact number of generations per year is not clear. First instar crawlers emerge in June, and there is a second generation in August. In Maryland adult males and females are present in September through October. Eggs, crawlers and adults are all present in the early to mid fall.”  Temperature differences here in the south probably have these dates moved up earlier.

Girdling roots can be a serious problem, especially if plants are left too long in a liner pot.  The picture shows a camellia.  In this case the roots are above ground.  They are often circled underground as well.  It's important to look for this before planting.

Albert Van Hoogmoed 

AL Dept of Agriculture, Mobile County

We receive many calls and visits at the Extension Office from people who have land and do not know what to do with it. "What can I grow?" is a very common question, and "It depends" is the most common answer. It depends on how much time you will have to work on the land, water availability, slope of land, location, available equipment, market, etc. Extension conducts many meetings every year discussing production practices for many different areas of agriculture including horticulture, forages and livestock, agronomy, pond management, wildlife management, etc. for the beginning or experienced grower. This Farming 101 program is specifically designed for the beginning grower, but anyone can attend. A beginning grower does not mean you have never grown anything. You may be a very experienced grower of peach trees, but a beginner at greenhouse lettuce. This program is to teach you the basic practices of growing certain crops. We have other meetings with more detailed information that are available for more experienced growers.

The Farming 101 program will held on Thursdays during the month of April at the Autauga County Extension office. The first meeting will be April 5th, and the last meeting will be April 19th. There will be two classes taught each day, one from 10:00 a.m. -12:00 p.m., and one from 12:30 p.m. – 2:30 p.m. Pre-registration is required, and the cost per class is $10 ($20 for both classes per day) or $50 for the entire course, and lunch will be provided each day. Please mail the registration fee to the Autauga County Extension Office, 2226 Highway 14 W, Suite E, Autaugaville, Al. 36003. If registering for individual classes, please indicate which class(es).

The classes on April 5th are Livestock Management at 10:00 a.m. and Forage Management at 12:30 p.m. On April 12th the classes are Basic Vegetable Production at 10:00 a.m. and Protected Production – (greenhouse and high tunnel) at 12:30 p.m. The classes on April 19th are Insect Pest Scouting and Management in Using Conventional and Organic (Bioinsecticidal) Approaches at 10:00 a.m. and Fruit Production at 12:30 p.m. Regional Extension Agents and Extension Specialists will be teaching these classes.

If you have questions concerning the Farming 101 program, please contact Darrue Sharpe at 334-361-7273 or Chip East at 256-846-0314. 

What a difference a year (and adequate chill) makes.  Unlike last year, when peach trees struggled to bloom due to the lack of chill, there is no shortage of blooms this year.  At last observation, (Monday, February 26), several peach varieties in the variety block at the Chilton Research and Extension Center were at full bloom such as 'Country Sweet', 'Glacier', 'Goldprince', and 'Juneprince' already there. 

Bloom is taking place earlier than in some previous years as well.  Though peach blooms are a welcome sight, their earliness this year presents some management challenges.  First, there is always the expectation of a late season frost.  Flower buds that have been released from dormancy will be vulnerable to damage. 

Secondly, another issue that we may face is blossom blight.  Blossom blight is a fungal infection of the peach flower.  The same fungus that causes brown rot - Monilinia fructicola, causes blossom blight.  Blossoms that turn brown after bloom is an indication of blossom blight.  Blossom blight has not occurred in the area recently or very often over the years but conditions are favorable for an occurrence of this disease.  Blossom blight could be an issue where brown rot cankers or mummies were found during pruning.  We are almost certain to see an increase in the number of mummies left on trees because of changes in tree management due to lack of chill experienced last season.  These mummies will serve as additional sources of inoculum and hasten the spread of blossom blight or brown rot.

According to the 2018 Southeastern Peach, Nectarine, and Plum Pest Management and Culture Guide, spay options for blossom blight are captan, chlorothalonil, thiophanate-methyl plus captan, Rovral and Vangard.  Again, Topsin M should always be combined with Captan.  Consult the pest management guide for rates and cautions.  If there should be a need to prune after pesticide application consult the pest management guide on worker safety, which can be found on page 11.  The pest management guide also suggests that insecticides not be included in tank mixes during bloom in order to protect pollinators.

Edgar Vinson

Extension Specialist, ACES


Insecticide shelf.JPGHave you ever wondered how insecticides sold at various stores actually work? Why are there so many different types of products in the market?

The simplest answer is that insecticides have a variety of modes of action and not all insecticides are suitable for the multitude insect pest species. While there are many different types of insecticidal formulations and packaging, there are four basic modes of action of organic and conventional insecticides, plus one separate category for insecticides with non-specific action. Below is brief description of each category. For detailed information, we strongly recommend readers to refer to the Insecticide Resistance Action Committee (IRAC) website that has very good educational materials for download.

  • Most common insecticides sold and used in the world today target the insect nerves and muscles. As many 12 IRAC Chemical Groups have nerve action. Many of them are contact poisons meaning insects die quickly from directed sprays. The nerve toxins include many old chemistries such as the carbamates and organophosphates. Think about Sevin, Lannate, Malathion, and Orthene. The old and new generation synthetic pyrethroid insecticides are also nerve toxins. However, the relatively new generation synthetic pyrethroid insecticide like bifenthrin are quick-acting and more photostable. Within the nerve toxins, there are slight variation in the actual action. Interestingly, new scientific discoveries have led to the development of neonicotinoid insecticides that mimic insect nervous system enzymes and products have systemic action. Another relatively new product line include high selective insecticides including Beleaf and Coragen that arrest aphid and caterpillar feeding by affecting special muscle receptors. Organic insecticides like Pyganic contain natural pyrethrin and they also belong to this category. Since there are many popular insecticides in this category, long-term use has led to the development of insecticide resistance that is a cause of major concern. If you don't see a product working well in your farm or garden, make sure to contact an entomologist or extension system in your state to manage resistance issues.
  • Another emerging group of insecticides that are relatively selective to target pest include the insect growth regulators (IGRs) with contact action on immature insects. Nearly seven IRAC Chemical Groups affect insect growth and development. Some insecticides mimic the juvenile hormone to stop insects growing while other chemicals inhibit the synthesis of chitin (or new skin) and disrupt the molting process. Some insecticides that are indirectly growth regulators include ones that will stop lipid production or some other action. Some popular products that are direct disruptors of insect growth include Knack for whitefly control, Zeal for spider mite control, Rimon and Intrepid for caterpillar control. Best effectiveness of these products comes from their timely usage when insects and small (immature) and low in numbers. Products will take many days to act and usually have a good residue on foliage for long-term control. Growth regulator insecticides will not work on mature insects. Research in Alabama and elsewhere has shown IGRs to be very good rotation partner with synthetic pyrethroids. Interestingly, the neem (organic insecticide) also disrupts insect growth but is not classified as such in the IRAC system due to the complexity of the active ingredient azadirachtin.  
  • About six chemical groups in the IRAC system are inhibitors of mitochondrial or cellular respiration with primarily contact action. Some of the more popular miticides belonging to this category, such as Portal, Acramite and Kanemite. Old organic products like rotenone that have been long discontinued also belonged to this group of electron transport inhibitors.
  • Bacillus thuringiensis, or Bt, is one of the largest selling organic insecticide that has a stomach action. In simple words, Bt proteins disrupt insect feeding and receptors in the insect midgut with long term effects. Bt products can be specific to certain types of insects such as caterpillars, maggots, and grubs, although many Bt products are not readily available at all times. Most commonly sold Bt products like DiPel, Javelin, and Xentari are effective against caterpillars. They have to applied to the foliage when caterpillars are small and given the time to fully act.
  • Last, but not the least, there are a number of popular products that have unknown modes of action or have multiple targets. One such product is neem (containing azadirachtin) which has antifeedant and growth inhibitor properties on small, soft-bodied insects.

For more details about individual IRAC Chemical Groups, visit For Alabama Vegetable IPM recommendations please refer to the IPM guides available on Alabama Vegetable IPM.

Insecticide effectiveness comparison.jpg

Ayanava Majumdar, Extension Entomologist and

State SARE Program Coordinator, Auburn University

LF logo.pngAre you a fresh produce farmer or food processor that supplies local markets?

If so, the Local Food Safety Collaborative (LFSC) wants to know how to help you enhance food safety in your operation.  We have recently completed a national needs assessment and are looking to refine ideas around what kind of trainings, educational tools, and resources YOU need.

We are inviting fresh produce growers and processors from Alabama and Mississippi for a facilitated listening session on Wednesday, March 21, 2018 at the Mississippi Minority Farmers Alliance located at 30122 Okolona Rd., Okolona, MS 38860.  A grower's session will be conducted from 10:00 AM to 12:00 noon and a processor session will be held from 1:00 PM to 3:00 PM.  Personnel from Cornell University will conduct/facilitate both sessions and lunch will be provided.

Farmers and processors who participate in the 2-hour session will receive a $125 stipend for their time.  Only 12 growers and 12 processors will be needed.

The LFSC was established to enhance fundamental food safety knowledge and support local farmers and processors to comply with applicable FSMA regulations.  We will use the information gained from our listening sessions to direct development of new outreach and education materials for local food producers.

To register and participate in the listening sessions, please contact Andrew Williams at or 334-216-1344.

The Alabama IPM Communicator is part of the Alabama Cooperative Extension System (ACES) where we are committed to providing you research-based information for improving farm income and the quality of life for all residents. The main purpose of this newsletter is to provide information about critical crop production and pest management information for a diverse range of crops grown in Alabama.

This newsletter promotes sustainable agriculture, i.e., successful farming without depleting natural resources so that future generations can have productive land for food production.

The Communicator is a great resource due to the professionals that share information. Research and Extension personnel from all education institutions in Alabama can submit crop production and plant protection articles of high relevance for immediate release. Outside media agencies are welcome to share articles published on this website.

Currently there are over 2,500 subscribers in the database, including many email groups. Growth rate for the subscriptions is about 10 percent yearly. Articles are published as blogs and PDF formats with links. The articles and newsletters are all archived by year, which can be accessed at any time. This archive can be found here.

On the Alabama IPM Communicator webpage, a calendar of local and out-of-state events with a link to the flyer is updated daily. The blog is also updated daily with timely articles and alerts.

We appreciate all continued support for the newsletter, and please inform us about any concerns or questions by contacting Ann Chambliss,

Everything you need on the dashboard of your truck.

The Southeastern Vegetable Extension Workers Group is proud to offer you the 19th edition of the Vegetable Crop Handbook for the Southeastern United States.

This handbook represents a joint effort among Extension Specialists and Researchers from 12 land-grant universities in the U.S. who work in the area of vegetable production. These specialists and researchers represent a wide array of disciplines: agricultural engineering, entomology, olericulture (vegetable production), plant pathology, postharvest physiology, soil science, and weed science.

This handbook comprises up-to-the-minute information developed from research and Extension projects conducted throughout the southeastern United States.  Download your copy at:

As growers receive results from their soil tests, I am commonly asked what is the difference between agricultural lime and gypsum.  The follow up question is usually "can I use gypsum to raise my soil pH?" The answer is no. 

Many soils in Alabama become more acidic over time. This is a natural part of how soils change over time. The processes of "liming" involves applying a material to neutralize that acidity. The most common product used is agricultural lime – calcium carbonate (CaCO3). Agricultural lime works by increasing the exchangeable calcium and neutralizing hydrogen ions. 

Gypsum is calcium sulfate (CaSO4ˑ2H2O). Gypsum has a neutral effect on soil pH.  This means that gypsum will not neutralize acid soils or effectively soil raise pH.

Both of these products, however, do provide a crucial plant nutrient, calcium.  The amount of calcium in each material differs with its purity and type. Gypsum also contains sulfur, another needed plant nutrient.

So, if you your soil test indicates that you need to raise the pH of you soil, agricultural lime is what you need.  The amount you need to apply depends on your soil test and the specific liming material you are interested in using (for example, calcitic lime, or dolomitic lime). If you do not need to apply any liming material BUT you do need to apply calcium, gypsum would be a potential choice for you to use. In the end, what you apply will revolve around cost as well as availability.  In any case, if you are unsure of what to use or simply what to go over your options, call your local Extension office or a State specialist like me. We are here to help.

Joe Kemble

Extension Specialist, Commercial Horticulture

Inspection Report Week of January 29, 2018

Now is a great time to check blueberries for scale.  They are easier to see on bare branches.

Florida wax scale (FWS) was seen on blueberries in a nursery during the growing season a few years ago.  They covered branches and a lot of the foliage before they were discovered. I also saw two FWS on blueberries in Bay Minette recently. The white scales were easy to spot on the purplish-colored branches.  FWS crawlers emerge around the middle of May and the middle of August.  The cameo stage (when they first form white covers) is the best time to treat.  This picture could be Indian wax scale. They both look similar, with IWS being bigger and having a softer wax cover.



FWS can also be spotted on jasmine and barberries now while the leaves are off.  FWS has a wide host range, so other plants should be inspected as well.

This Indian wax scale was seen recently in a planting of blueberries.  They appeared mostly on older wood but also some new wood.  I'm not sure when crawlers emerge.  A North Carolina site mentions treatment in early June.  Flagging an infested bush and watching for crawlers is the best way to go.  Handpicking to remove scales also works if there are not very many.



More information can be found at this site:


In the future, moving boxwoods into Tennessee and into Alabama may become a little more difficult.

This past Friday at the Gulf States Horticulture Expo, ALNLA set up a grower meeting where the Department of Agriculture discussed their response to Tennessee's fast approaching boxwood quarantine. This quarantine is scheduled to go into effect on February 4th. Once the quarantine goes into effect, any boxwoods that are headed to TN will be required to have a phytosanitary certificate and compliance agreement. Christel Harden, the administrator for the Plant Protection Division with the Department of Ag, recommends contacting your plant inspector ASAP if you plan on shipping boxwoods to Tennessee in the near future.  

Over the next few months, Christel will be working to get a quarantine passed for Alabama. An Alabama quarantine will allow for easier shipping to other quarantined states and go a long way in protecting our growers and landscapes; however, it will make bringing any boxwoods into our state more difficult.  There could be numerous scenarios associated with compliance agreements and no level of planning can cover every situation. With that in mind, it is important to patiently with the Department of Ag as we all navigate through these changes.  

Jeremy M. Pickens

Extension Specialist and Research Scientist

Ornamental Horticulture Research Center

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