Although weeds are considered invasive because they quickly spread to other areas, some produce yellow and orange flowers that make them somewhat attractive. In fact, varieties, such as the butterflyweed, are purposely grown in gardens because the yellowish-orange blossoms attract butterflies. The blooms, along with the other plant features, are key to helping you successfully identify weeds with these coloured flowers. Know the variety that you encounter to determine whether you want to keep it or not.
Write down the environment, such as a lawn, where you see the weed with the yellow and orange flowers. Weeds such as the orange hawkweed, as an example, are commonly found in full-sun locations including roadsides, pastures and gravel pits.
Watch to see when the orange and yellow blossoms appear on the weed plant. The butterflyweed, for instance, blooms from May to September.
Look to see how the weed's yellow and orange flowers are growing on the stems. For example, write down whether the blossoms grow in clusters or if they appear as singles on the stem.
Record the leaf characteristics including the shape and texture. Weed varieties such as the coast fiddleneck contain narrow foliage that resembles a spear shape and is covered with stiff, needle-like hair.
Search through an online plant database to identify the plant by its characteristics.