You're probably safe with M.x giganteus. In his first book, Darke said it rarely self-sows, and in his second he said what appears to be a misprint:

"Trials have confirmed that it does not produce sterile seeds, and therefore it must be propagated by division"

I think he meant to say it does not produce fertile or viable seeds.

Anyway, try it. Keep in mind, it's known to frequently lose it's lower leaves during the course of a season, so if you don't want to look at bare canes, you'll have to plant something else to mask them.

It isn't, however, the tallest grass you can grow on Long Island. Both Arundo donax and Saccharum ravennae will grow taller, although both can be invasive under perfect conditions.

Looks like they are both on the invasive list, and although the soil may look unfertile, I have been putting leaves and grass clippings on the hill which would create the perfect place for seedlings to emerge.
Any thing else donn?
The grass will be at the base of a hill and then up the hill for erosion control. I like the look and sound of the grasses as they move. As the train goes by a slight wind is created which would move the grass gently.

The hill/slope goes down to the LIRR track. Most of my neighbors have retaining walls. At a cost of over $30,000.00 I think I will go with plants.
Grasses I believe would work well on the hill which is sandy and easily erodes when walked on. The roots are deep
I can divide them and have more quickly.
Any ideas are greatly appreciated.
Cherry, Long Island

Panicum (Switch Grass) is one of the taller grasses native to Long Island. It's a sod-forming grass, loves sandy soil, and once established, is quite drought tolerant. You can buy plugs of very attractive cultivars, like 'Heavy Metal' and 'Northwind' and divide them fairly early to increase your collection. You can also grow species Panicum virgatum, and P.v. 'Strictum' from seed, but they will be more apt to self-sow. Switch Grass is frequently used for erosion control and dune stabilization.

I think I'd look into using a variety of grasses, instead of just one. There are lots of lower growing varieties suited to your area and conditions, and a nice mix of them would be very attractive.

I agree with Donn. I'd try a mix of grasses that are good erosion control stabilizers. Panicum and Leymus would be my suggestions. Perhaps a few Erianthus (Saccharum). Leymus Blue Dune is shorter, but mixed in would work well as a stabilizer and tolerates drought like the panicums. Perhaps starting off the hill with shorter Leymus, stepping up into Panicums. Panicum Dallas Blues is one of my favorites and will be at least 5 feet or more.

Do I plant them now or wait till spring?
I guess I could WS some but would it take too long for them to become esthablished?
which ones are easiest to grow from seed? I am not a master WS,yet.

The Leymus blue Dune makes me a bit nervous because it spreads by rhizomes do I need to be concerned or is it easy to pull out? I don't want it to take over the whole area and crowd out my native flowers.
Cherry

Both Leymus and Panicum send up new shoots from spreading rhizomes, but I like to refer to these types as clumping spreaders ( hey, an oxymoron :) ).

Santa Rosa Gardens says this about Leymus Blue Dune, "Best used in open areas, but can be contained with minimum effort." It's the matting rhizomes that help stabilize the sand and control erosion, so you give up one, you give up the other. If you are filling with other flowering natives and want to contain it to a small area, Leymus may not be right, as it willl likely spread some, even with the dry, sandy conditions.

What's nice about Blue Dune is that it's a cool season grass that's tolerant of hot weather. You could start both Leymus and Panicums this fall.

You could also try to find some wildflower seed mixes, and possibly seed out virgatum as well. Plugs are always easier on a sandy, dry hill, but with some attention, seeding could work. Donn is quite a seed master and may have some advice in that area.

Here is a link that might be useful: Leymus Blue Dune

I don't think I'd advise starting any warm season grasses from seed this late in the year. By the time you get germination, it'll be time for them to go dormant, and I'm afraid you wouldn't get them well enough established to hold the slope through winter. Cool season grasses would be no problem, because they'll keep developing roots right into December.

Don't try direct seeding the slope unless you plan to invest in some protective matting or geotextiles to keep the seeds and seedlings in place. I'd probably start plugs in cell trays, and look to plant them out in October/November. If you've got a 2-3" root system, you have a much better chance of keeping them in place. You can even fasten a plug in place with an earth staple made of coat hanger wire.

Here's a photo of a hillside covered in Leymus Blue Dune

Here is a link that might be useful: {{gwi:867121}}

Very striking photo!

I took an assessment of the grasses I have. I have Panicum Shenandoah, Moudry Fountain grass Pennisetum alopecuroides Moudry it is the first season I have it bought it at Lowes on the discount rack, Zebra grass about 6 small clumps that my friend gave me, and a grass with very skinny "leaves" that are rough(very common here on Long Island).

I am confused about when to plant the grass seems some need fall planting and some need spring planting. I would like to buy some of the ones you recommend any good sources?
Cherry

If you're putting in actively growing pots of grasses, I'd try to give them 4 to 6 weeks of establishment time prior to first frost. A typical first frost in your area is mid to late October, but could come as early as late September. If that's the case, it is close. I think you have time to plant decent sized grasses, but smaller plugs/clumps would probably be a problem. Donn's going to have a good feel for safe planting times in that area. It comes down to how lucky you feel and what plants you're willing to lose.

Be aware that Pennisetum Moudry will probably seed out over the hill after a few years. THat may be what you want, but in an untended planting Moudry can come back to haunt you.

Several good sources online to buy grasses. This forum has lots of recommendations. Here's just a few...

Santa Rosa Gardens
Plant Delights
High Country Gardens
Bluestem Nsy
Digging Dog Nsy

Don't mean to exclude any retailers, but these seem to be reputable grass sellers.

Thanks.. I think I will pull up the moudry grass.
Thats what happens when you don't research tht plants and buy on a whim.
I may plant it down by the railroad tracks. I am excited to buy some grass.. hmm that sounds a bit funny.
chery