First of all, ticks are everywhere. Including lawns. Tick denisties vary by region and impervious surfaces. Essex and Middlesex county are leaders in the state for tickage. In the woods, they are more commonly found in the thick leaf litter, especially oak. In lawn, well, the grass.
Ticks cause Lyme disease. In people and pets (such as dogs).
Lyme disease symptoms in people can vary widely. A person may be diagnosed with chronic fatigue syndrome, allergies, the flu or a basic skin rash. One person I know was slammed with every symptom in the book, including Bells Palsy (where half the face is paralyzed). Another friend was misdiagnosed for years and suffers permanent nervous system damage. And a note about the bullseye rash. It doesn't happen as often as people think.
If you think you might have been exposed ( ie, symtoms, imbedded tick or realization that you are super outdoorsy but never been tested), require that your doctor test for Lyme. Yes, you will probably get some resistance due to not being familiar with circumstances, but do it. UMass Amherst will test the tick for Lyme if you prefer that route. The antivirals prescribed are very heavy duty and are meant to crush the first stages of Lyme.
Tell your doctor if you are in a higher risk position (environmental professionals, search and rescue, chronic campers) . Make him/her put it in the file. Sounds odd, but even though my physician knew about my career, she never made the connection of being high risk. I assumed she knew.
As for dogs, my parent's dog, Molly, reacts by having very occasional seizures. The vets don't know why, but the seizures seemed to help control the disease in her. My dog, Kirby, shows no symtoms at all and is being monitored for changes. It sometimes settles in the joints, so take note if your pup still seems oddly arthritic a week after a walk. There is a vaccine, but it can't be administered if the dog is positive for Lyme.
You can't get Lyme from other people or dogs.
Spring and fall ticks dig deeper into the flesh than summer ticks.
Last of all, and perhpas the greatest misconception, ticks to do not have a season. They are temperature sensitive. If it is warm enough (even for 2 days) for yardwork to be comforatably done in a sweatshirt, the ticks find it comfortable enough to do their work.
To answer an unasked question. I do not have Lyme, but nearly every one of my environmental collegues does.