The entrances to ant nests often have a surface cone of excavated soil and ants can usually be seen using the burrow. Unfortunately, some burrow-dwelling spiders, including funnel-webs, also pile excavated soil on the down-hill side of their burrow after the burrow has been inundated by a period of wet weather.

Some moth caterpillars and other insects make densely webbed masses in green vegetation. The larvae of certain insect species also lay down webbing in masses of decaying plant material then make pupal cases that look like the egg sacs of some spiders. The web mass produced at the bases of some gum trees by Symphyta larvae is remarkably similar to the entrance to a funnel-web burrow.

Webs seen on damp lawns may be made by fungi. The strands of such 'webs' are always short like animal fur and quickly disappear when the lawn dries out. The soft parts of plants frequently become mouldy as they decay and this will sometimes lead to the growth of fungal mycelia that have a superficial resemblance to spider's web.

Not all flat webs found on lawns are due to either spiders or fungi. Occasionally, insect larvae will produce a relatively large area of webbing that appears quickly and disappears almost as fast, the larvae themselves rarely being seen because they form the web during the night. This kind of web usually differs from that of a fungal web in that the latter typically appears as a ring not as a solid area.

Few, if any, spiders lay unprotected egg masses so eggs not enclosed in webbing of any kind are more likely to have been laid by an insect than by a spider. Neuropteran (lacewing) insects produce single eggs (or U-shaped rows of eggs) on stalks but these hatch very quickly and the life cycle of these insects is very short when compared with that for most spiders. Some insects lay batches of eggs encased in white material but this probably will not look like spider silk and presumably serves to impede desiccation of the eggs. A good example of this is the white egg patch of the common hemipteran planthopper that typically lays its eggs on smooth tree trunks.