While they might look like your typical pinecone at first glance, these creepy bagworm cocoons found in Ontario are actually jam-packed with hundreds of tree-killing eggs that have the potential to defoliate evergreen plants across the province.

Bagworms attack mostly deciduous and evergreen trees, including cedar, fir, hemlock, juniper, pine, and spruce. The spine-chilling insects spin cocoons in its larvae life, decorating it with bits of plant material from trees on which it feeds. 

The cone-shaped bags are usually interwoven using silk, bits of leaves, and twigs from its host plant. After the larvae hatch, they have the potential to disperse to surrounding plants, putting nearby trees at risk.

Adult females usually spend their entire lives inside their bags and are wingless, while adult males have wings and develop into freely flying months. 

The problematic pests have already made a comeback in the province, with sightings of the nasty tree invaders only increasing throughout the years.

Since complete defoliation and plant death can often result from the pest, you might want to get rid of it as quickly as possible; however, simply throwing them away or stepping on them won't necessarily suffice or kill the hundreds of eggs in the sack. 

If detected early, these cocoons can be removed by hand and placed into a plastic bucket filled with a mixture of warm water and dish soap. Make sure that the sacks are fully submerged before proceeding. 

Next, you'll want to dump the soaked bagworms into a sealed plastic sack and throw them in the garbage. 

Although this can be done at any point during the season, it's critical to do so before the new generation of bagworms hatch — which usually occurs in late May to mid-June.

You can also treat bagworms with an insecticide that contains Bacillus thuringiensis, a bacteria that is deadly to young bagworms.