Crabgrass (Digitaria sanguinalis) and Goosegrass (Eleusine indica) are two prevalent grassy weeds that often grow side by side in lawns, gardens, and fields. Their similar appearance can make them difficult to distinguish at first glance. However, by closely observing their growth habits, leaf characteristics, and especially the thinness of their seed head spikes, you can easily tell them apart. In this article, we will focus on these defining characteristics, particularly honing in on the thinness and structure of their seed heads, which can be one of the most telling features.
1. Crabgrass (Digitaria sanguinalis) Identification
Crabgrass
Crabgrass is often considered a nuisance weed due to its fast-spreading nature. Its mat-like growth can quickly cover large areas, crowding out desirable grass species. Here’s how to identify it:
Growth Habit:
- Crabgrass grows horizontally along the soil surface. Its stems spread outward and root at the nodes, which makes it spread quickly.
- It tends to form a dense, sprawling mat, with stems lying flat on the ground and extending outward like tentacles.
Leaf Characteristics:
- The leaves are broad and slightly hairy, with a rough texture.
- A central vein is pronounced, and the leaves are typically flat against the ground.
- The color of Crabgrass is generally a lighter, more vibrant green.
Seed Heads (Spike Structure):
- Crabgrass seed heads have a characteristic “finger-like” appearance, resembling the spread of an open hand.
- Each finger-like spike radiates from a central point, and the seed heads usually contain 3–7 spikes.
- The spikes themselves tend to be somewhat thick and bushy due to the density of the seeds on each spike.
- Compared to Goosegrass, Crabgrass seed heads appear coarser and fuller, giving them a more robust, disorganized appearance.
- While the seed spikes of Crabgrass are not particularly thin, they do have a rough, textured look due to the clustering of seeds.
2. Goosegrass (Eleusine indica) Identification
Goosegrass is another common weed, often found in compacted soils like athletic fields and driveways. It differs from Crabgrass in several key ways, including its seed heads, which are notably thinner and more organized.
Growth Habit:
- Goosegrass grows in an upright, clumped, and rosette-like fashion.
- Rather than spreading horizontally like Crabgrass, Goosegrass forms dense tufts or bunches and has a more compact appearance.
Leaf Characteristics:
- The leaves of Goosegrass are narrower, smoother, and often shinier compared to those of Crabgrass.
- A distinct feature is the silver-white base of its leaves, which makes it easier to spot when closely observed.
- Goosegrass leaves grow more upright, creating a tighter bunch compared to the flatter leaves of Crabgrass.
Seed Heads (Spike Structure):
- One of the most noticeable differences between Goosegrass and Crabgrass is the seed head structure. Goosegrass has seed spikes that are much thinner, more delicate, and organized.
- The seed spikes are arranged in a flat, finger-like pattern, with two rows of seeds running along each stem.
- Goosegrass seed heads appear more structured and refined, with a neater, “tidy” look compared to the bushy seed heads of Crabgrass.
- The thinness of the seed spikes is a key feature—each spike is considerably narrower and more elongated than the thicker spikes of Crabgrass.
3. Key Differences in Seed Head Thinness and Structure
Understanding the structural differences between the seed heads of Crabgrass and Goosegrass can significantly improve your ability to identify these two weeds.
Crabgrass Seed Heads:
- Seed spikes are fuller, bushier, and radiate outward like an umbrella from a single point.
- The spikes are not particularly thin, but rather thicker due to the dense clustering of seeds.
- The overall appearance is more chaotic and less refined, with the seed heads often looking rough or fuzzy.
Goosegrass
Goosegrass Seed Heads:
- The spikes are thinner and more delicate, giving them a fine, elegant appearance.
- Goosegrass seed spikes grow in a more organized and symmetrical pattern, with two distinct rows of seeds running along each stem.
- The overall appearance is more structured and clean, with the thin spikes making it look more compact and refined compared to the coarser Crabgrass seed heads.
4. Color Differences and Additional Identification Tips
Color can also be a helpful factor in distinguishing these two weeds.
- Crabgrass is generally a lighter, vibrant green, and its leaves have a rougher, slightly hairy texture. The stems tend to have a reddish hue near the base.
- Goosegrass is darker green, with a silver or white base at the center of its leaves. This gives Goosegrass a glossier, more vigorous appearance.
5. Key Points for Field Identification
- Leaf Texture and Color:
- Crabgrass leaves are broader and slightly hairy.
- Goosegrass leaves are narrower, smoother, and have a distinct silver base.
- Growth Habit:
- Crabgrass spreads horizontally, forming a wide mat.
- Goosegrass grows upright in a rosette-like formation, appearing more compact.
- Seed Head Spikes:
- Crabgrass seed spikes are thicker and bushier.
- Goosegrass seed spikes are thinner and more organized, giving a neater appearance.
By focusing on these differences, particularly the thinness and structure of the seed spikes, you can easily differentiate between Crabgrass and Goosegrass in the field.
Conclusion
While both Crabgrass and Goosegrass can be nuisances in lawns and gardens, their subtle differences—especially in the appearance of their seed heads—make them easier to distinguish once you know what to look for. Remember, Crabgrass seed heads are fuller and bushier, while Goosegrass seed heads are thinner, more delicate, and orderly. Along with leaf texture, growth habit, and color, these characteristics will help you easily identify and manage these common weeds.
