Planting to prevent erosion

I am going to build a 30 foot long Hugelkultur with the logs and brances from 4 standing trees that died to due recent drought her in eastern Oklahoma. My soil is clay then rock. Thus I will be adding soil, manure and compost. I see much info about building the mounds, but I'm still not clear on covering the mound and planting to prevent erosion. My worry is that with rains it will erode the soft materials added to the mound.
- What would be good to plant to get thing started first year?
Is the concept to cover the mound with mulch or have cover crops all the time like clover? This is new to me Ive only row planted my gardens up to now.

Well timed question. I was just walking my dog under the full moon and looking at an eye high eroding bank. So I will speak now about erosion into the sea. This particular spot is run wild with invasive. The grass may be native - I'm not sure, it pokes up and grow long tall stalks with soft velvety seed heads - the rest is super thorny. And It has been slipping into the sea about as slowly as possible - which is pretty damn quick.

To give you an Idea of what I was looking at. The topsoil for about 8 inches including a HUGE rock about the size of a large torso was being held up despite having been undercut by about 2 feet. The entire rock was undercut and free hanging supported only by the topsoil. This was tall grass and English ivy. Lots and lots of creeping ivy. There are several small golden chain trees (which came sometime in the distant past of 40 or 50 years ago from the grandaddy of all golden chain here at my place) and way way lots of thorny rose hips I'm not sure which type. The rose hips and trees where back from the bank by a bit but I imagine their roots form a matrix most of the way to the bank. In other locations I've seen Himalayan blackberry doing its damnedest.

I'm sure having anything planted which deadens the punch of the rain and slows its soaking into the earth as well as having a good root system would work to help mitigate erosion. I sure hope we don't need to cover the earth in English Ivy and thorny brambles.

Edit: You changed the content of your post! Now that I re-read it What I describe would probably not be relevant to your situation. Hopefully someone else here has got more experience in a similar setting!

Edit 2: Re-rereading It I would once again say: having anything planted which deadens the punch of the rain and slows its soaking into the earth as well as having a good root system would work to help mitigate erosion. this means thick dense canopy and thick root system even if the canopy is only 6 inches of the ground (like a creeping mat of ivy). Grass and other rhizomorphic roots would strike me as being a decent ticket too

Stinging nettle if you're climate will support them spread by rhizomes. Stinging nettle and strawberry and lemon balm are 3 plants I have had some success growing together. The lemon balm forms very thick clumps while the nettles and strawberries seem to choose to have more room to themselves.

If erosion from rain is the concern; it seems that a low growing clovers works rather well.

Mulch is good, but mulch does not hold soil against erosion. It reduces evaporation and it softens the impact of rain, but of itself it does not hold soil.
So, yes, you should mulch. But also yes, you should plant. You can plant cover crops, but you can also plant productive crops. No reason not to plant food crops along with nitrogen fixers and other green manures. You want the huge covered with growing stuff, whose root systems will hold the soil in place and whose leaves will minimize the impact of rain.

Thanks for info. Primary purpose for producing vegetables. I wondered if just planting vegetable plants will keep mound from eroding. I am thinking about planting white clover all over then putting vegetable plants into that. Or just planting vegetables alone will work.