Dogs Learn How to Sniff Out Cherry Disease

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Modern dogs tend to be pets rather than working animals. However, the latter is still around. To name an example, there are the ag dogs being trained in East Wenatchee, WA. That part of the state is famous for its orchards. As a result, interested individuals should be able to guess that the ag dogs are being trained to work with trees in some way.

What Are the Ag Dogs Being Taught to Do?

Specifically, the Wenatchee Kennel Club is teaching dogs how to find little cherry disease. There are two components to the program. First, the participating dogs are brought to a cherry orchard where parts of LCD-infected trees have been tied to their uninfected counterparts. They are taught to sniff out these parts when they are given the command word “cherry.” If the participating dogs are successful, they get a treat to reinforce their behavior; if the participating dogs are not successful, they can be taught again and again until they get it right. Second, the participating dogs are brought to the Wenatchee Kennel Club’s training center so that they can compare their skills with those of a machine specifically designed to find LCD. This part of the program sees them sniffing their way through two sets of six identical-looking cans. Each set contains one infected sample, four uninfected samples, and one can containing nothing whatsoever, thus making for more of a challenge than otherwise possible. So far, the participating dogs seem to be showing good results.

How Is This Possible?

Different senses provide different information. Even so, this doesn’t mean that every sense is as useful for an animal as every other sense. Instead, some senses are more useful than others and vice versa, which is why different animals have evolved different sensory capabilities. For an extreme example, consider troglofauna that are adapted for living in caves. It is very common for these species to lose their eyes because said organs use a lot of energy while providing either no or next-to-no benefits in total darkness. Furthermore, a lot of troglofauna have lost their pigmentation for much the same reason.

In any case, dogs are a species with a very good sense of smell. Going by PetMD, their nose can be up to 100,000 times better than ours, thus making them so much better at sniffing out things than humans that we struggle to understand it. The example used by the same source compared a dog’s sense of smell with the ability to detect 1/2 a teaspoon of sugar in an Olympic-sized swimming pool, which is so remarkable that it sounds more ridiculous than anything else. On top of this, humans have been busy breeding dogs to become better and better at sniffing things out. After all, they have been our hunting companions for a very long time, so much so that this is either the first or one of the first ways that they started helping us out. As a result, dogs have been bred for this purpose for millennia. Granted, not every hunting dog was bred to hunt using their sense of smell.

There is an entire group of dogs called sighthounds, which are named thus because they were meant to keep their prey in their sight the entire time using their speed. Having said that, it isn’t a coincidence that some of the dogs with the best senses of smell are so-called scenthounds. For example, Beagles are smaller scenthounds meant for hunting hares and rabbits. Similarly, Bloodhounds are bigger scenthounds meant for hunting boars and deer. The sense of smell that makes these dogs useful for hunting has made them useful for other things as well. Search and rescue is an excellent example. However, dogs are also seeing use for detecting everything from drugs to diseases. There are other options for each of these things. Even so, dogs are very useful because they are so much more accessible than most of these other options. That accessibility plays an important role in the Wenatchee Kennel Club’s decision to train the ag dogs.

Why Are the Ag Dogs So Important?

Washington State University says that LCD isn’t a new problem in the Pacific Northwest. The first major outbreak in the region happened in Canada’s Kootenay Valley in 1938, which was so bad that the last of the packing lines closed down in 1979. Even now, the cherry industry in Canada is still recovering from it. The cherry industry in Washington has fared better. It saw its first major outbreak in the 1940s and 1950s. Then, the removal of huge swathes of infected trees stemmed the tide. Unfortunately, LCD made a return in more recent times with the result that it has been a problem for the cherry industry in Washington ever since 2010. LCD doesn’t kill the infected trees. Instead, it makes for fewer cherries, smaller cherries, and blander-tasting cherries. As a result, LCD has a devastating effect on the profitability of infected trees. This is particularly true because both varieties of the virus responsible for the disease can be spread via grafting. Furthermore, one of the two varieties can be spread by apple and grape mealybugs as well. In other words, if an orchard owner isn’t vigilant, they could see LCD spread throughout their orchard. Ag dogs are useful because the detection of LCD is much easier said than done. In the first and second years, the signs might be limited to certain branches and clusters. It isn’t until the second and third years that the infection has become systematic enough to become extremely obvious. Even so, if people suspect the presence of LCD, they need to send a sample to a laboratory for testing if they want to be sure what is going on. Ag dogs promise to make it much easier for them to pick up on the presence of the disease. In turn, that should enable people to take corrective action sooner rather than later, thus limiting the extent of the damage.