Drosera tokaiensis habitat

[Khelljuhg]

About a month ago, I visited a Drosera tokaiensis habitat on an agricultural path in Mitoyo City, Kagawa pref., Japan. The D. tokaiensis was barely alive due to the summer drought, which is an old tradition in this area (usually the ground is wetter in the rest of a year). The local people used to remove the tall weeds regularly, and this would unintendedly help the Drosera to thrive (there used to be a glittering red carpet on the ground!). However, these days the path seems to be nearly abandoned, and the habitat has been diminishing because of the resulting intrusion of larger plants.

Usually, D. tokaiensis habitats in this region are very small, but each strain of the species seems to be unique, perhaps because of separate evolution resulted from the dry climate.

And this is something a bit closer to how it should look (but more light needed):

And here are some photos of plants I found just around the D. tokaiensis spot:

Platycodon grandiflorus

Millettia japonica

Deinostema violaceum

Isoetes japonica

Potamogeton sp. and Utricularia tenuicaulis (the U. tenuicaulis is hardly visible in this photo)

[Daniel O.]

Hi,

nice pictures.

Interesting to see the natural habitat of D. tokaiensis, it really seems to be relatively dry.

Thanks for sharing.

Best regards,

Dani

[Khelljuhg]

Thanks, Dani!

The summer dought sometimes dries out all the D. tokaiensis plants in this place (the whole region has been known for droughts). The Drosera in this spot seems to produce seeds by midsummer and get ready for the drought, and it resumes its growth when the temperature is lower and the water comes back. Perhaps I should have visited the site earlier or later (and not in the middle of hot summer) so that I could have found healthier-looking D. tokaiensis, but unfortunately there was no chance. In any case, other plants have started to cover the Drosera, so this habitat may be lost in some time.

[Daniel O.]

I hope that this location will last for a very long time , it´s always very interesting to see Drosera in the wild.

On what altitude are they growing there and how hot is it getting there during summer?

Have you also seen the parent plants (D. rotundifolia and D.spatulata) there after it´s the natural cross between them or has somebody sown them out at this location?

Best regards,

Dani

Edited September 24, 2008 by Daniel O.

[Khelljuhg]

I hope that this location will last for a very long time , it´s always very interesting to see Drosera in the wild.

On what altitude are they growing there and how hot is it getting there during summer?

Have you also seen the parent plants (D. rotundifolia and D.spatulata) there after it´s the natural cross between them or has somebody sown them out at this location?

Well, the altitude must be below 100 metres, and the summer temperature is often obove 32 degrees C (this summer, the temperature once went up to 37.5 degrees C).

Actually, D. spatulata has not been discovered in this region, although I have seen D. rotundifolia in another place. D. tokaiensis is believed to be something derived from a hybrid between D. rotundifolia and D. spatulata a very long time ago by doubling of the chromosome number. It is fertile by itself, so it is not the case that D. rotundifolia and D. spatulata cross in every habitat.

D. rotudifolia X spatulata does occur where there are both species, though, but the resulting hybrids are triploid and sterile like D. x obovata. Moreover, it is not very common that D. rotundifolia and D. spatulata are found together, because of the difference of requirements.

[bouncingwatermellon]

I've never heard of Drosera in Kagawa. Weird to find it in that area, considering how the region receives so little precipitation year round due to it being sheltered from monsoon winds by mountains to the north and south.