Anywhere in Washington, Oregon, Idaho, Montana, Wyoming, Utah, Colorado, Southern British Columbia Hobo Spiders can be found. We feel that it is likely that there are Hobos in Northern California. We have also received spider samples from the many parts of Mid-West and North Eastern USA which appear to be Hobo spiders.
The hobo spider creates a non-sticky (in spider standards) trip web that doesn't permanently stick insects to the web. Instead, once the prey trips on the web the hobo spider attacks the prey before it can get away. This along with its poor eye site explains why they are noticeably more aggressive to humans then other spiders. They have to attack to eat otherwise they would die of starvation.
Their webs are funnel shaped and are often attached to an object in the yard--by the foundation--between planters, or anything that remains stationary near the ground level. It also makes webs under the siding of homes and attaching to plants or weeds.
Here is an example of a large hobo spider web--20% of actual size. Most
webs are not as obvious and large, these are pictures taken between 2
planters for new trees.
To the left is a picture of a Hobo Spider bite. About 50% of Hobo Spider bites are 'dry,' meaning that no venom is injected, and nothing happens to the victim. Often times the victim does not even realize that he has been bit.
Typically, when venom is injected, the victim will experience an immediate redness which develops around the bite, then begins to disappear within a few hours. Very often, for the first 24 hours, the bite appears to be no worse than that of a mosquito; then it begins to blister in the center. Within 24 to 36 hours the blister breaks open leaving an open, oozing ulceration.
This ulceration 'scabs' over within three weeks from the initial bite, leaving a permanent scar. If the bite is delivered in fatty tissue, the lesion may be very deep and extensive and not heal for two or three years. Systematic reactions to Hobo Spider poisoning include severe headaches, nausea, vomiting, soreness, and flu-like symptoms.
In extreme cases where the bite was not taken care of early, skin graft,
amputation, and the possibility of bone marrow failure may occur.
Pre-baited traps have shown to be the most effective means available to control Hobo Spider populations.
In order to kill Hobo spiders with pesticides you usually have to hit the spider directly with large doses. The problem with non discriminate spraying is that you kill the good competitor and predator spiders and insects and thus make more room for the more mobile and hardy Hobo spider. This will often lead to a worse problem with Hobo spiders as one man witnessed in 1997 in his own home.