Let’s See How Fast Cattails Grow

2020 August 9

Just down the hill from our house, there are a number of bogs that are filled with common cattails, Typha latifolia (also known as bulrushes). I’ve always been impressed by how fast they grow, and thought it would be nice to document it. So:

Starting on May 12, 2020, here is what the largest bog looks like. This was just a short time after the last of the snow melted. Everything is mashed flat and looks dead.


12 days later, on May 24, it still looks pretty dead, but there are a lot of shoots coming up.


Just 3 days later, on May 27, it has already gotten significantly greener, although there are still some mashed parts. The bigger cattails are starting to overtake the ferns and horsetails in the foreground.


By June 12 (16 days later), the cattails are getting pretty serious. They are now all over 3 feet tall and are seriously dominating the area.

June 22 (another 10 days) and we have tall, lush cattail growth, the leaves are mostly around 5 feet tall, which is close to their maximum growth.


And, by July 13 (another 21 days) the cattail fronds are well over 6 feet, and we are getting the flowering heads coming up. So, total elapsed time from flat wasteland to towering plants with flower heads is only 62 days, or almost exactly 2 months.


Here’s a closeup of the flowering heads and the leaves. The spike on top is the pollen-producing male flowers, while the part that looks like a hot-dog is the closely packed female flowers. When mature, these will turn into massive poofs of parachute seeds.


Anyway, these are found in wetlands around the world, compliments of their seeds being able to parachute for miles and miles and miles. They grow pretty much everywhere that has shallow standing water year-round, and once established they keep coming up from the roots (which I understand are edible). They are one of the prime markers that a particular piece of land is a wetland. And, as you might gather from the growth rate here, their biomass production rate is pretty high. If you choose to harvest the cattail tops, I understand you can get between 4 and 6 tons of biomass per acre (although, harvesting is complicated by the fact that they grow in the swamp, and so the odds of a harvesting machine getting stuck are pretty high).

3 Responses
  1. Carole permalink
    August 9, 2020

    Around here, Florida, cattails are an indication of nutrient load. Lots of nutrients from septic tanks, sewage treatment release or fertilizer from yards and agriculture… you get cattails. Low nutrients, in Florida, you get sawgrass.

  2. August 30, 2020

    Well done with the photography! Much dedication.

    One of my projects once the growing and harvesting season is over will be to make an Arduino time-lapse camera thingamabob to take shots of my various planter boxes as they develop. I never have the discipline to take the pictures that you did.

  3. October 11, 2020

    Surely they are known as bulrushes (in the UK too) but I believe what you have there is Greater Reedmace.
    My old boss (who did a Master’s on the aquatic fungi that decompose Typha leaves) told me that the confusion with actual bulrushes arose from artists including the striking reedmace flowers in paintings of the infant Moses, but I don’t know if that’s true.
    Keep up the good work; your posts are keenly followed. (Came for the macro photo tips, stayed for the joy in natural history.)

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