Adventures in Organic Gardening

The fourth honey bee disease on the list for the Apprentice Level Exam for the Texas Master Beekeeper Program is Chalkbrood.

Chalkbrood isn’t as scary as American Foulbrood, European Foulbrood and Nosema. Chalkbrood is a fungal disease. There isn’t really a treatment for it, but the bees usually get rid of it through their normal hygenic behavior. Cases are usually seen in springtime especially when it’s damp and cool. The name comes from how the dead larvae get all white and chalky and swell to fill the cell in which they’re located.

Adult bees clean up the chalkbrood and get rid of the disease. In fact, the white mummies fall to the bottom board of the hive where you can see them. If it seems to be persistent, requeen for better stock that will keep things nice and tidy in the hive.

So there you go! Next: Sacbrood!

Here are a couple of helpful links:
Texas Apiary Inspection Service Article on Chalkbrood
Helpful YouTube Video on Chalkbrood

I’m really glad that on the study guide for the Texas Master Beekeeper Apprentice Level Study Guide that they put honey bee diseases as the first section. It’s really upsetting to study all of the various things that can wreak havoc with our precious hives, so I’m eager to plow through this and get on to studying more about these fascinating creatures.

Previously we looked at American Foulbrood, and then European Foulbrood.

Next on our hit parade of bee maladies is the dreaded Nosema. There are many different species of Nosema (different strains affect different insects), but only two that affect honeybees. Nosema Apis, and Nosema Cerana. The latter has only affected European honeybees only recently. Cerena is more damaging and kills bees faster than Apis.

Nosema is a disease of the gut. It’s the result of a microsporidian parasite that gets ingested by the bees and damages their digestive ability. It’s generally always around, but the hive can run into trouble during the times of year that conditions are ripe for Nosema to build up inside the hive and therefore more readily become ingested by the bee population.

Besides a generally sluggish colony just not doing well, signs you can keep an eye out for when thinking of Nosema include a number of things. Bees crawling around on the ground in front of the hive can suggest Nosema. The condition known as “K Wing” where the two sets of wings spread out and suggest the letter “K” on top of the bee is also something to watch for. Probably the biggest and most obvious tell tale sign for Nosema is fecal staining on the outside surface of your hive. It looks like brown or yellow drips. The bees get dysentery as they are infected with Nosema. Nosema seems to peak in late winter when the bees haven’t been able to take cleansing flights out of the hive and the spores just build up and build up.

The only way to absolutely diagnose Nosema conclusively is with a microscopic examination.

The standard treatment for Nosema is to feed syrup mixed with fumagillin. I did find an interesting article by Randy Oliver that talked about a drench treatment as well.

Here is a good video on the subject.

Next: Chalkbrood!

In my continuing quest to be prepared for the Apprentice Level Exam for the Texas Master Beekeeper program, this is the next entry in my series of study guides. As a reminder, here is the list of what you need to know for the apprentice level exam.

Yesterday’s article was about American Foulbrood

Today I am studying European Foulbrood. While it’s still dreadful to have anything associated with your bees that starts with the word “foul”, European Foulbrood is the not quite as dreadful one to get. Oh, and by the way, the only reason one is “American” and one is “European” has to do with an American person identified the American one, and…you guessed it….a European identified the subject of today’s study.

European Foulbrood is another thing to keep in your mind when you discover a scattered brood pattern. European Foulbrood doesn’t make spores (like American does) so that makes it easier to control. This bacteria gets into the brood food and is eaten by the larve. Then it competes for food with the larve which understandably causes problems for the larve. And, if varroa didn’t already cause enough problems, they are spreaders of EFB. Just another reason to be vigilant with your mite control.

I read that there appears to be a relationship to the ratio between nurse bees and larva and the incidence of European Foulbrood. During a big nectar flow, more bees are assigned to “worker” status so there are less nurse bees. This creates a situation for EFB to take over. When the ratio corrects itself, the problem will likely be corrected.

When Larvae die from European Foulbrood they curl up, change color from that glorious glossy white to yellow or brown. The dead larvae will feel rubbery. When the larve die, the workers don’t cap the cell, so that’s why the scattered brood pattern is a big clue.

The best way to keep European Foulbrood out of your life is to keep a generally healthy hive. If you start to notice a problem, you can treat with antibiotics and you can also requeen your hive for more hygenic behavior by the bees.

Here are some good articles on European Foulbrood

Beeinformed Article on European Foulbrood

Texas A&M Article on European Foulbrood

I am registered to take the test to be designated an Apprentice Level beekeeper which is the first step in becoming a Master Beekeeper in the State of Texas. I will take the test in November in San Antonio at the Texas Beekeepers Association Annual Convention. The program provides this study guide, but I haven’t been able to find a comprehensive place to find all of the actual information. So, I decided to create one. This is the first in a series of articles I’m writing where I pull together the information on each section of the test.

Please understand that I have not taken the test and am currently studying for it. I don’t know what will actually be on the test. Watch for another article where I’ll summarize the experience of taking (and hopefully passing) the exam.

The first section on the study guide covers honey bee diseases. The process of studying this section feels a little bit like watching a medical show where you become anxious that you could possibly have every malady they discuss. As I’ve been studying these diseases I find myself thinking “Have I seen that in my hives?”. In fact, I did a short hive inspection this morning and had my eyes peeled for today’s subject which is American Foulbrood.

American Foulbrood feels like probably the worst thing you could have in your hive. By the time you actually SEE American Foulbrood in your hive, it’s too late. You have to burn the hive, the bees and all of the equipment. There’s no getting over it. Certainly something you want to avoid.

Spotty Brood Pattern:
When you see a spotty brood pattern, consider American Foulbrood. That’s the first sign. Of course it could also be just a failing queen or something similarly fixable. Do keep your eyes out for the rest of the signs.

Sunken Cap:
American Foul Brood kills the larve under the cap. After the larve dies, the cap sinks in.

Greasy Looking Cap:
The cap over affected cells also can develop a greasy sheen.

Perforated Cap:
After the larve dies, the cap sinks and looks greasy, the nurse bees try to take care of the mess and poke holes in the cap to try to clean out the cell. Don’t be worried when you see a hole in a cap caused by a bee being born. That’s different.

Once you spotted the signs listed above there are a couple of more steps you can take to verify the presence of American Foul Brood. (Of course, to definatively diagnose requires a lab test.) For one thing, you can stick a match stick into a sunken cell and draw out the liquified larve inside. If it makes a string (a rope) of at least 1/8 inch when you pull it out, that suggests American Foul Brood. Then you should look for “scale”. Scale is the dark dried larve after it has sunk to the bottom of the cell. Remember that looking into the bottom of the cell when the frame is upright means you should hold the frame by the top bar and look across the foundation.

Here are some helpful links that include photographs and videos for further information on American Foulbrood.

Bee Informed Article on American Foulbrood
Michigan State University Article on American Foulbrood
Texas A&M Article on American Foulbrood (Great video, too.)