After the organizer was infested with ticks while scouting out trails at the Wachusett Reservoir, Tower Hill Botanic Garden decided to cancel Thursday evening's scheduled Worcester Tree Initiative nature walk.

Derek Lirange, who was to lead the walk on the reservoir property with Ruth Seward, found 23 ticks crawling on him while checking out the one-mile route he was planning to take, according to Ann Marie Pilch, education director for Tower Hill. The walk was scheduled for 6 p.m.

"With that many ticks, I just did not feel comfortable holding it," Ms. Pilch said.

The walk was planned as a look at the tree growth near the reservoir and what has grown up after trees were removed due to Asian longhorned beetle infestation.

This year is expected to be especially bad for ticks and the diseases they carry, according to the Centers for Disease Control. Ms. Pilch said she has not seen many ticks at Tower Hill or where she has been hiking this year. She said she was surprised at the number of ticks Mr. Lirange found on his short walk. With that level of tick population in the Wachusett Reservoir area she said she does not think the hike can be rescheduled.