Hi everyone! So me and my wife bought a house 2 years ago and it has a bamboo "grove" towards the back of the property. It is around 25' across and pretty circular. The mature stalks are about the thickness of a pinky finger at their thickest point and 10-15ft tall. As you can see from the pics the grove is pretty tightly packed. When you look into the grove it appears as though 5-10 stalks grow upward within inches of each other, then there is a 1-2' between patches of stalks.
I am wondering if anyone could help me find out if this is clumping or running bamboo. I have dug some of it up and it seems to have traits of both. I have dug up many patches/shoots that have multiple culms growing out of the patch and then turning directly upward, which makes me think clumping. However, I have also seen some shoots that have grown radially outward from the main patch that have one culm every 6-10" along its growth. This makes me think it is a running type. A lot of these shoots appear to have been culms that have come up out of the ground and then turned downward back into the ground and continued growing as a shoot.
Most of the clumps/shoots I have dug up are less than 6" underground. Most the the shoots I can pull straight up out of the ground as they are less than 3" deep.
My neighbor has lived in the house next door since she was a kid and now owns it and is currently in her late 40s. She also has some on her property. She said her mother, and the lady that used to own our house planted it (~5-8ft around at the time) about 20-25 years ago, and the lady that owned my property never really trimmed it, just let it grow.

I am not sure what the deal is. To me, it almost seems like it is a clumping bamboo that "runs" until it finds enough daylight and then it forms a clump. Because this grove is so old, the overhang and shadow of the mature stalks tilts outward many feet from the center, causing the surrounding ground to be in shade a few feet from the edge of the grove. My neighbors bamboo is even more tightly packed then mine, but she has trimmed over the years so it is much smaller grove with less "overhang".

Clumping, running? A running bamboo that doesn't run very far/fast since it is a temperate climate? What do you think?

I think you can safely label that a clumper. If that's a runner, it wouldn't be that size after 20 years of neglect. But like you said, it can also be one that exhibits both traits because not everything is black and white. However, judging from that root clump you hold up, it is very much a clumper.

Looks a lot like Pseudosasa japonica, which is sometimes said to have both running and clumping characteristics, but maybe someone else can say for sure.

_________________
God Bless,

Matthew

===============================

Genesis 2:8 And the Lord God planted a garden eastward in Eden; and there He put the man whom He had formed.

A runner for sure.

_________________
Brad Salmon, zone 5b/6 Southern Indiana
Winters -20 to -25C. Summers 30 to 35C , humid. 115 cm annual precipitation, frost free from May through early October. 259.3 meters elevation. Growing 150+ species. http://www.needmorebamboo.com/

Leptomorph.

_________________
David Arnold
Middle Tennessee Bamboo Farm
USDA zone 6b/7a

Thats what someone else told me.

what I have done so far this year, was I went to the furtherest "clump" of culms and used a mallet to carefully dig them up. When I lifted them up I was able to follow the rhizome back to the next "clump" towards the main grove. I was also able to see if the clump I dug up had a rhizome(s) that was underground leading away from the main grove.
Ideally I would like to get this grove to about half the size... maybe take 5-8ft off the entire perimeter. A couple of questions:
Can I plant grass ontop of the lopped culms? I know the roots are so shallow, I am not sure if I will be able to grow "regular" lol grass ontop of the dying/dead roots.
If I wanted to dig up and completely remove the 5-8ft off the perimeter I would do it over time (a month or so). Would it be best to cut all the culms down at once and make the grove the size I want it and then dig the roots out that are outside that area over the course of a month or two. Or would it be better to just cut down a few clumps of culms and then dig them right up? I guess I am just worried if I cut down the culms to the area I wanted, would the bamboo go nuts sending out rhizomes?

Also, Thanks again for all the help. I spent 6 years in Hawaii and grew to love bamboo, but we have a pretty big yard with alot of stuff going on already (pond, garden, veggies..etc) So I dont really have time to maintain a 30' bamboo grove.

My neighbors has been kept in check by her thru digging and pruning and it is so much smaller than mine lol.

Some photos indicate it's running, but some of them show short clumping characteristics. I too think it must be one variety of Pseudosasa japonica. They can spread vigorously, but they are usually tightly clumped. Since their rhizomes can go quite deep, if needed, total control can be tricky, but not nearly impossible.

Really? Almost "clump" I have pulled up the clump and rhizome have been less than 6" deep. Most of them I was able to pull straight up out of the ground. It did help that the ground was soft from the rain today.
Most of the things I read about them online said that the Japonica are runners, but rather slow runners

I am also on Long Island so it is on the colder side for this type of bamboo, so maybe that slows its growth a bit?????

I just came in from outside... its horrible here, cold and drizzling. I spent about 1-1.5hrs going around the entire perimeter cutting down culms. I cut from 3-5ft inward on average around the entire grove. There were a couple impressive shoots 4-6ft tall... however most shoots were under 4-6" tall. I would say over 90% of new shoots that I see coming up are within a few inches of existing culms. That makes me feel a bit better about the running rate of this bamboo. The grove does look better already, it looks a bit more upright than it was before. I will probably go out there and trim it in another 3ft or so all the way around and then dig my trench. I have to see how much the wifey wants me to trim back first before I trim too much, lol.
I got rather lucky... my 30lbs australian shepherd runs around and around and around the grove all day long... it used to make me wonder what is wrong with her! lol. However I now have a 3-5" rut around the entire grove which is how I was able to see the rhizomes in the first place, lol. Who would have thought.

Definitely looks like Pseudosasa japonica to me. My grove of it is six years old and has hardly spread.

_________________
Southern Indiana. Theoretically the same climate as 'needmore' & 'Eastlandia'.
My Bamboo List.

"Take Dog apart. Disinfect. Reassemble."

Did you do anything to contain it?

No, I let it run free and it just sat there.

_________________
Southern Indiana. Theoretically the same climate as 'needmore' & 'Eastlandia'.
My Bamboo List.

"Take Dog apart. Disinfect. Reassemble."

Any advice on cutting this back some? Id like to make the grove about half the size it is now.

Get a machete and start hacking it down (horizontally) as low at the base as possible. Don't worry about regrowth. Chances are they wouldn't grow again this year (if they're done shooting). Then just mow it down every shooting season their after. Might want to take out the weak and ugly looking ones in the middle if you can.


ps. I have never actually done it myself...but it makes sense.

If i keep mowing down the outside of the grove will that cause it to send out rhisomes even further?