You’ve turned in after a productive day of gardening.  Beginning to doze off, you feel something ever so slightly brushing against your thigh.  You reach and feel a small hard object crawling up your leg.  Lights on.  It’s a tick, ambling along looking for a nice warm place to suck your blood!  Enough Stephen King.  Ticks are gross but sometimes unavoidable if you are a gardener. Yet in addition to being unpleasant they can also be dangerous.  The Centers for Disease Control list at least sixteen serious infectious diseases that can be transmitted by ticks in the United States, including Lyme disease and Rocky Mountain spotted fever.

So what are these guys and how do they manage to get on your skin?  Ticks are arachnids, insects that are second cousins to spiders, members of the Ixodida family.  Like many insects they go through egg, larva, nymph and adult stages.  At each stage of life they need a blood meal to survive.  Most aren’t picky as to whose blood they drink, selecting mammal, bird, reptile or amphibian hosts as they pass through their life stages.  Also they aren’t picky as to what’s in the blood they drink, ingesting whatever assorted bacteria or viruses the host happens to have.  Ticks can’t jump or fly but they can wait patiently on a blade of grass or leaf, latching on to whomever happens to be passing by.  Once on board, the tick settles down on a promising spot and inserts a feeding tube. In the process it often secretes saliva which can contain whatever infection the tick has picked up from its previous host.  If all goes well (for the tick) it will feed for several days and then drop off to begin its next life stage and find its next victim.

The deer tick (blacklegged tick) below is much smaller than the wood tick (American dog tick) above and to the right.  The lone star tick on the upper right is occasionally seen in Minnesota.

Although there are about a dozen species of ticks in Minnesota, two types commonly spread disease.  They are the deer tick or black legged tick and the wood tick or American dog tick.  Of the two the deer tick is by far the most common disease spreader, transmitting Lyme disease among other things.  Wood ticks may spread Rocky Mountain spotted fever and tularemia but most bites thankfully are unpleasant but harmless.

There are a number of things you can do to lessen the chance of picking up one of these fellows.  First of all avoid wooded and brushy areas with high grass or leaf litter.  Walk in the center of trails when you are out in the woods.  If you can’t avoid these high exposure areas consider treating clothing and gear with 0.5% permethrin.  It is available as a spray or you can even buy pretreated clothing and gear.  The Environmental Protection Agency suggests use of insect repellants such as DEET, picaridin, IR3535, Oil of Lemon Eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone.  They advise against using OLE or PMD on children less than three years old.

After a day out in the garden or the woods, it's best to shower down and then carefully check your body, clothing and gear for ticks.  Don’t forget to check the family dog too!

The life stages of the Blacklegged (deer) tick, lone star tick and American dog (wood) tick demonstrating their relative sizes.

If you do find an attached tick, remove it with a pair of fine tipped forceps (tweezers). Grasp it as close to the skin as possible.  Pull up with steady, even pressure.  Don’t jerk or twist it as this may break off the mouth parts, leaving them in the skin.  If this does happen remove them with the tweezer tips.  After removing the tick, clean up the bite with rubbing alcohol or soap and water.  Never crush a tick with your fingers. 

If you do develop a rash or a fever within a few weeks of a tick bite, see your health care provider right away.  Be sure to tell him or her about the bite, when and where it occurred.

Want to learn more?  The CDC has an excellent site.

Also check out this Minnesota Department of Health article. 

And read this article from University of Minnesota Extension’s entomologist, Jeffery Hahn. 

Photo credits: Minnesota Department of Health (1, 2)