Identify Weeds

This page breaks down the common traits
unanimously agreed on
to identify weeds.

Click for different weeds and their identification.

When soil is exposed, weeds grow first.
Widespread.
Better ability to survive over other plants.
Better at getting water, sunlight and soil nutrients where it can crowd out other plants.
Less vulnerable to insects, diseases and various climate conditions.
Better at multiplying than most cultivated plants.
Spreads quickly, making control harder.
Weed seeds germinate more easily over other sided plants like annual flowers.
Can grow, even thrive in most soil types, especially poor quality soils lacking nutrients.
Aggressive stolons - Above ground runners, as with Field Bindweed, where new plants can start.
Aggressive Rhizomes - Underground creeping roots where new plants can start when it comes to weeds, rhizomes take over quickly.

Weed stems grow up faster crowding out wanted smaller annuals and perennial plants from needed sunlight.
Aggressive rhizomes use up water, nutrients and oxygen where wanted vegetation can't get them.

Allelopathy: Poisonous to plants.

Allelopathic plants release chemicals to other plants to kill them. This can be done from the roots or washed into soil from fallen leaves.

If there is a constant ring of exposed soil where nothing ever grows is a good indication that soil is a hostile environment for anything to grow. An example of this is Quackgrass.
Poisonous to humans and animals.

Can create rashes, as with leaves of three weeds like Poison Ivy.

Poisonous to ingest such as weeds like Poison Hemlock and Pokeweed.

If cows ingest White Snake root (Eupatorium rugosum) the milk can kill anyone who drinks it.
Cause unwanted reactions to pollen.

Pollens can cause hayfever and allergic reactions as with Ragweed and Bermuda Grass.
Bad Hosts

Insects and disease that spread to other garden and lawn plants. For example, Pokeweed can host Cucumba Mosaic, a viral desease that can spread to cucumber crops.