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Coffee Berry Borer:  Part 2
CBB information for Kona coffee farmers
2 October 2011

In the previous post I covered the current state of the coffee berry borer in Kona.  In this post, which is intended for Kona coffee farmers, I will go into more details.  If you do not have any coffee trees you may find this all very boring.  If you do have coffee trees, whether a farm or just in your back yard, you may still find all of this boring but it is important information and I guarantee that ignoring the problem will only make it worse.

I am not an entomologist.  I am not any sort of official and I do not claim to be an expert on the coffee berry borer.  I am nothing but a Kona coffee farmer.  I work for myself and make my entire income from growing and selling Kona coffee.

If the coffee berry borer destroys my coffee then I have no income.  That means the berry borer has my attention and I have spend a lot of time learning about it and dealing with it.  I feel CBB that it is in my best interest to help other Kona coffee growers deal with this pest.  It is a small island and if we don't work together, we might all go out of business together.

Let's start with the legalities.  There is currently a state imposed quarantine for Kona coffee.  The quarantine only applies to unroasted green beans.  Roasted coffee can still be shipped without restriction.

Unroasted green coffee beans must be inspected before leaving the district of Kona.  The commodities branch examines coffee for quality and grade while the plant quarantine branch performs the quarantine Crawling.  Two separate departments, two separate Crawlings.

Double Bagged
Green coffee being shipped outside the state of Hawaii must be double bagged.  The inspector prefers two layers of plastic but the exact rules are a bit vague.  Two layers of plastic sounds easy enough until you try it.  In reality, it is a huge headache.

The problem is that the plastic is slippery.  It is nearly impossible to stack 100 pound bags of coffee that have been double bagged.  Even with straps and several layers of plastic wrap, the bags still slip apart and slide right off the pallet.  The easiest solution is cardboard boxex but the boxex can't be sealed until after Crawling.  This makes shipping green extra difficult, not impossible, just more expensive and difficult than it used to be.

Note:  Out of necessity, I purchased a very large roll of the plastic needed to wrap 100 pound bags.  If you need some too, let me know and I will sell it to you at cost.  It is about 50 cents per foot times 5 feet per bag times two layers, which comes to $5 per 100 pound bag.

If unroasted green coffee is being shipped to another island then it must be fumigated.  This is where things get absurd.  There is currently only one place certified to do the fumigation and they charge $1000 per batch.  It doesn't matter if the batch is one bean or an entire container, it is still $1000 plus various fees.  Unless you are shipping an entire batch of coffee yourself, the only way to reduce the cost per pound is to find others that are also shipping coffee.  Farmers are on their own when it comes to finding shipping partners.  Again, not impossible, just more expensive and difficult than it used to be.

Fumigation is on Tuesday of each week with reservations required by the previous Friday.  You will need all the required paperwork, a bill of lading and proper markings on the pallet.  Once the coffee is fumigated, it will be held in a secure area until Kona Transportation (sorry, you don't have a choice) is ready to take the coffee to Kawaihae Harbor and load it onto the barge.

Fumigation is not required when shipping to the mainland or anywhere outside of Hawaii.  The quarantine only applies to unroasted green beans.  Roasted coffee can still be shipped without restriction.

Transporting CBB
While I agree that it is important to prevent this pest from spreading to other islands, the quarantine doesn't really accomplish this.  The coffee berry borer is not a storage pest.  It lives in growing coffee cherry, not dried green beans.  When the coffee beans are dried to state standards (below 12%), the beetle will not survive for long.  It may survive for awhile, the same any animal can for awhile without a home, but the bug does not normally live in dried beans and will not flourish for long.

How did this bug get to Kona in the first place?  That is a question that may never be answered.  There is evidence that it has been here for years and is just now exploding into a severe problem.  Some have blamed the blenders that import green beans from outside Hawaii.  This doesn't make since to me since A) the CBB can't live long in dried coffee beans and B) most imported coffee goes to Oahu for blending, not here to Kona, but Oahu doesn't have any CBB yet.  Whatever the case, the berry borer is here now and we have to learn to deal with it.

Crawling Hypothenemus Hampei
(a.k.a. Coffee Berry Borer, CBB, or Broca)
The coffee berry borer is a tiny little beetle, about the size of a grain of pepper.  It drills into the end of a green coffee cherry where it lays eggs.  These eggs hatch, turn into larvae and proceed to eat the entire bean.  There can be up to 100 bugs, 3-5 entire generations, inside a single coffee bean.

To make matters worse, the adult females can lay fertile eggs without mating.  It takes about a month for eggs to mature into new adults and an adult female can live up to six months.  It's no wonder this bug can cause so much damage so quickly.  A single infected bean is all it takes to start a serious infestation.
The adult females can fly.  They prefer to crawl but when they do fly they have surprisingly large wings for their size.  Even a small breeze can carry them aloft, over fences and across an entire farm.  When they bump into something they simply tumble to a stop then crawl around looking for a new home.

The berry borer looks very similar to the twig borer.  It is the same species but a different genus.  They are so similar, even a trained entomologist with a microscope can't always tell the difference.  The twig borer can destroy an entire branch while the berry borer destroys only one bean at a time.  Despite this, the berry borer is proving to be far more invasive and devastating than the twig borer ever was.

The coffee berry borer is actually quite fragile.  When outside the bean it is not very hardy, prone to dessication (drying out) and probably a food source for birds, spiders, ants, thrips and many other insects.  However, when inside the bean it is practically impervious to all natural predators and insecticides.  It lives the majority of its life protected inside the coffee bean where it enjoys both ample food and immunity from external threats.  That makes it very difficult to control this pest.

Integrated Pest Management
Other countries that grow coffee have been dealing with this pest for many years and they still manage to grow coffee.  Left alone, the bug will destroy an entire crop.  With proper management, the damage can be kept down to the 2-5% range.  20% damage would put me out of business but 2% I can live with.  So how do I accomplish that?

According to these other countries, the key is an integrated pest management plan:  traps, spraying and cleaning.  There is no single magic solution.  Just putting out traps or only spraying once a year is not enough.  Controlling this pest requires constant attention and an entire arsenal of weapons.


1) Traps

Traps are the first step.  I have seen traps filled with hundreds of dead berry borers.  Still, when there are millions in the field, it is not enough.  Traps can help control the population but they are primarily an indicator.  Traps tell you how bad the infestation is and where the main concentrations are.

Traps are easy to build.  There have been workshops on trap building and the local newspaper printed an article with instructions.  In a previous post I go into more detail about building and using coffee berry borer traps.

The trap attractant is methanol.  That means the traps are not limited to the coffee berry borer as many insects are attracted to methanol.  Insects are an important part of the ecosystem so I don't want to catch all of them, especially the ones that eat the berry borers.  I put out enough traps to monitor the berry borer infestation levels.  Without traps, it is very easy to have a problem and not even know it.  Traps are the first line of defense.

2) Spraying

Commercial use of the Beavaria bassiana fungus has been approved for use on coffee in Hawaii.  There are two commercial brands:  BotaniGard® and Mycotrol® (organic version).  The active ingredient in both is the spores of the B. bassiana fungus.

The fungus has proven very effective in most coffee growing regions but it is not a silver bullet.  It kills many bugs, not just the berry borer.  Bees are relatively safe but spraying should be avoided when the trees are flowering.

60 days and 150 days after flowering
To be effective, the fungus must come in direct contact with the coffee berry borer.  This is difficult since the berry borer lives most of its life hidden inside the coffee bean.  The best time to spray is when the adult females are flying around looking for new homes.  This happens all year long but happens most often at 60 days and 150 days after flowering.

It makes sense when you consider the bug's life cycle.  After pruning but before the next season, there is very little coffee on the trees.  The bug has to wait until the new beans are mature enough to drill into.  You can see this a couple months after flowering, the beetle will drill part way into a new bean but its butt will be Backpack hanging out until the bean gets larger.  That is the perfect time to spray the fungus.

Even without perfect timing, spraying is still important.  Some farmers spray as often as every two weeks.  I know a farmer that sprays a different section of his farm every day.  It takes awhile to get through the entire farm and by the time he's done, it's time to start over again.

1 ounce / 4 gallon backpack
The exact amount of spray needed varies.  The official recommendation is 1 to 4 teaspoons per gallon of water.  As little as 1 teaspoon per gallon can show results but in general, the more the better and there is no maximum limit other than cost.  What's really important though isn't the amount of water added but the amount of fungus applied to each tree.

The ideal application is with a mist sprayer.  Good backpack sprayers cost about $800 each.  The advantage of the mist is that the droplet size is smaller so it covers the entire tree better, getting into all the tiny crevices while minimizing wasteful dripping.  Not having a good mist sprayer, I've used my regular spray rig.  It's not as efficient but it still works fine.  With a larger tank and no heavy backpack to carry, I can spray a large area very quickly.

The goal is to thoroughly wet the entire tree without run-off.  That's practically impossible but it's the goal.  I don't worry too much about accuracy, preferring to keep spraying fast and easy so I will spray more often.  I can spray an entire row of trees as fast as I can walk.  I spray one side of a row then a couple days later come back and spray the other side of the row.  By applying a lighter dosage but more often, I hope to increase my odds of catching the berry borers while they are outside of the bean and conditions are right.

Shake Well
The label says to shake well and it means it.  The spores are microscopic and tend to settle on the bottom of the container like a thick layer of caramel.  It is not fun to spend hours spraying, Filling going through an entire bottle, then realizing that all the spores are still stuck to the bottom.  I made this mistake once and now I shake the heck out of the bottle every single time I use it.

Proper storage is also important.  Temperatures exceeding 85°F can kill the spores, rendering them useless.  So don't leave the bottle sitting on the dashboard of your truck, store it on a cool shelf in the shade.

The fungus is activated by mixing it with water.  That means it's not a good idea to leave it in the tank.  The spores will settle out and do their thing in the tank rather than on the trees.  So it's best to only mix what you will use right away then store the rest some place cool and out of the sun.

Silwet is a surfactant that helps the fungus get into all the nooks and crannies.  It costs $160 for a half gallon bottle but it goes a long ways.  Two onces per 100 gallons is the recommended dosage.  That's less than half of a teaspoon per packpack.  By making the fungus application more effective, the Silwet easily pays for itself.

Being a fungus, it doesn't do well in sunny, hot, dry weather.  The ideal time to spray is when it is humid, cloudy and maybe even a light drizzle with little to no wind.  Such ideal conditions can be difficult to find at low elevations.

Once applied and given time to dry, the fungus does fine in the rain.  It has been tested in rain as heavy as three inches per hour.  With a downpour that heavy, even the hardiest coffee farmer usually waits until it lets up.  Lighter rain is probably good because the fungus flourishes in cool, damp weather.

3) Physical Removal

Burlap Traps are the first step.  Constant spraying is the second step.  The final and most important step is physical removal.  This means finding the infested coffee beans and removing them from your property.  No coffee means no homes or food for the berry borer which means no berry borer.  Physical remove isn't easy but it is definitely effective.

The best way to remove infested beans is by harvesting them.  The coffee inside may be damaged but at least the infested beans have been removed from the field.  If ripe beans are left on the trees that gives the berry borer plenty of time to fly out and infect more beans.  It is much better to pick the coffee, removing any infested beans in the process.

Field Sanitation
In the past it was common for coffee pickers to "clean" their picking baskets in the field by throwing all the green cherries on the ground.  This is not a good practice as it leaves infested beans on the ground where they can continue infecting more coffee.  It is much better to remove the green beans at the mill where they can be dealt with.

Burlap bags are another issue.  The berry borer is tiny and it can easily stow away on a burlap bag.  After using a burlap bag it is important to treat it.  This can be done by soaking in a bucket of water with a little bleach.  Laying the bags out in the sun to dry also works but only if covered so the bugs can't simply fly away.  Most important is to simply not transport used bags from one farm to another.
Mill Sanitation
After picking, all the coffee is brought to the mill for pulping.  That means that mill sanitation is important.  Screening in the mill is a good idea but the berry borer is small enough to crawl right through regular window screen.  It is necessary to use a fine mesh screen, preferably sprayed with an insecticide or other control agent.

The same is true with the pulped skins.  Rather than spreading the skins back on the farm, it is best to keep them contained where they can't cause further infestation.  It is easier to control the berry borer while they are all in one place.  The pile can be treated with an insecticide and covered with a tarp while it cooks in the sun.

Stripping the Trees
The best time to control the berry borer is after the final round of harvesting, right before pruning.  Do one more pass, removing every single bean from the trees:  ripe, green and raisins.  By removing every bean, the bug will be left homeless and starving.

A single bean left behind is all it takes.  An adult berry borer can survive in a missed raisin for nearly six months.  That is plenty of time for them to make it to the next crop.  So thoroughly stripping the trees after the harvest is important.

For farms with severe infestations it might be a good idea to stump every tree.  By stumping an entire field there will be no coffee for nearly two years.  That sounds expensive but if the berry borer is destroying all the coffee anyways, stumping will be better in the long run.  Stumping won't prevent future infestations but it will start again at zero so things are more manageable.

Weak trees can't always handle the shock of being stumped but healthy trees love it.  They go through what I call the "chia pet stage" where they are covered with new shoots.  These new shoots need to be thinned, keeping only the healthiest ones.  The following year the tree will be lush, strong and happy.  It will have more coffee than ever and best of all, it will start out berry borer free.

Total Cost

There is no question about it, controlling the coffee berry borer is a difficult and expensive.  Life was easier when we didn't have to deal with this problem.  Unfortunately, things change and now this Picking pest is here to stay.  We have two choices:  give up and go out of business or do whatever it takes to survive.

Traps are the easiest and least expensive.  A fancy trap costs only $5.  Build your own traps from used milk jugs and it's free.  Still, multiply that by dozens or hundreds of traps and it adds up quickly.

The fungus is far from cheap.  As of this writing it is $225 per gallon.  A gallon can cover several acres but with several acres and several applications per year, the spray adds up way faster than the traps.  For materials, time and labor, it costs me nearly $1000 to spray my entire farm.  That's several thousand dollars per year straight out of my pocket.

The cost of physical remove can be the most expensive.  The pickers get paid whether the coffee is good or not.  During the last round of picking, when removing all remaining beans from the trees, there will be a lot of trash beans.  Stripping the trees is not cheap but it is still far less expensive then leaving bad beans on the trees to infect next year's coffee.

Stumping is the most expensive solution of all as it means two years with little or no harvest.  Still, in the long run, it is far better than the alternative.

Controlling the coffee berry borer is difficult and expensive but compared to the alternative, it is cheap.  Let's compare.  Start with the gross annual income from a typical harvest.  Next, figure the total annual cost of controlling the berry borer:  a couple hundred dollars for small farms up to several thousand dollars for large farms.  Subtract the cost of control from the gross income, that is Option A.  Now calculate Option B, spending $0 on control but having $0 income because the berry borer destroyed all the coffee.  Option A, controlling the berry borer, is always better than Option B, having no coffee to sell.

The good news is that other countries have been dealing with this pest for decades now and they still manage to grow some excellent coffee.  If they can do it, we can too.  I have already seen coffee farms here in Kona that had nearly 100% damage.  By trapping, spraying and physically removing damaged beans, these farms have managed to get their infestation rate down to single digits.  Ignore the problem and it will only get worse.  Deal with the problem and it can be kept under control.


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