I mention on the website that the seemingly obvious fact that grass is a plant can be both informative and instructive. To expand on this, let us consider an example. Did you know that the highest form of plant that grows in the ocean is algae? Even the giant kelp forests off the California coast are forms of algae. Why is this important? Well, it highlights the fact that the majority of higher plants cannot tolerate salt. Keeping in mind that grass is a plant therefore explains why those lawn areas on your property that see a higher than normal salt accumulation, such as places where street snow is ploughed, or run-off from heavily salted walkways accumulates, often exhibit poor, unhealthy growth. In other words, since grass is a plant, and most plants do not like salt, grass in areas of heavy salt accumulation tends to be weaker, sickly or just plain dead. The solution? Well, since our problem is salt, the solution is not to fertilize, aerate or re-seed. The solution is to both dilute and reduce the amount of salt in the area. Aside from eliminating salt from your winter snow management regime, try watering more heavily in salt-impacted areas, and adding gypsum to help leach salt from the soil.
Relatedly, among those of us who work with plants, there is a general rule that the roots of a plant often mirror its foliage (and vice versa). For instance, very twiggy, multi-stemmed shrubs often have shallow fibrous root systems. This fact is highly relevant to lawn care. If you want long roots that penetrate deeper into the soil, and are therefore better able to keep cool and moist, you ought to allow the foliage to grow longer and, in the case of your lawn, cut it higher. In short, grass with longer leaf surfaces, tends to have longer roots. Scientifically, this makes sense: grass is a plant; plants use sunlight in photosynthesis, the end result of which is the production of carbohydrates, which feed the root system and allow it to grow. How do plants collect sunlight? They do so with special photoreceptors on their leaf surfaces. If you think of a blade of grass like a solar panel, it makes sense that longer blades of grass—like larger solar panels—collect more light energy, and therefore add more fuel to the process that ultimately results in stronger root growth. Of course, there is a limit. Grass that is so long that it shades out its lower leaf surfaces is—like stacking one solar panel on top of another—not going to perform well. As a general rule, try cutting your lawn to maintain it at 3” rather than 1.5”. Additionally, longer grass can help combat weeds both by depriving their seeds the sunlight they require to germinate, and by out-competing low growing weeds for sunlight.
In summary, recalling the simply fact that grass is a plant has led us to two important points:
- Grass is weaker and sickly in salted areas because, like all other plants, grass does not like salt. To address the issue we need to both dilute and reduce the salt in these areas by watering and adding gypsum.
- Like other plants, a lawn’s roots mirror its foliage. Longer foliage means longer roots, which help the grass cope with heat and drought.
There are a host of other inferences one can make from the simple fact that grass is a plant, but I’m not giving away everything now, or you’ll never read another post. In all seriousness though, the next time you encounter a lawn issue, remind yourself that your grass is a plant, and think about what follows from that simple fact.