Help to ID plant and grasses

I've been waiting for this plant to flower but nothing yet. I believe it is a weed but want to be sure before removing it. Could anybody ID it?

I am also showing two pictures of the grasses in my lawn. I want to overseed but want to be sure to grab the right seed. In some areas there are clumps of other type of grass quite different and don't want to make the same mistake. The two look somewhat alike but one is taller and with a blade thicker than the other. Anybody here?

Thanks

 

Looks sort of like a Tamarisk with something like a watermelon vine around it.

 

The vine around is a zuchini. My plant does not look like other tamarisks pictures I found online. For instance, the pictures show that tamarisks are woody while my plant is not. Besides, seems that tamarisk does not grow in my area (Nebraska), Any other idea?

What about the grasses?

 

It looks like scentless chamomile, Matricaria maritima. Here's a link:http://www.agf.gov.bc.ca/cropprot/weedguid/chamomil.htm

 

Zucchini is a squash whereas your plant looks quite like a melon vine.

 

I agree with Ron, your vine does not look like a zucchini. And the plant you are asking about looks almost like a Cosmos that hasn't bloomed for whatever reason (too much fertilizer can cause some plants to grow lots of foliage instead of flowers). The grasses...sorry, I have no idea.

 

Could be Asparagus

 

Asparagus is very feathery and has a weeping growth habit, this plant is too upright and not feathery enough.

 

You are right Wild-rose-43, I had some Cosmos seeds that threw there long time ago, but I have not really fertilized a lot in that area so, is there any other reason with the Cosmos may not bloom?

Regarding the vine, I already have fruits. I planted both cantaloupe and zuchini and both are growing (unless it is not really a zuchini but a similar shaped squash!

 

Zucchini plant

http://images.google.com/images?hl=en&ie=ISO-8859-1&q=zucchini+plant&gbv=1

Watermelon plant

http://images.google.com/images?um=1&hl=en&c2coff=1&ie=ISO-8859-1&q=Watermelon+plant

 

I don't know why your Cosmos won't bloom. I've never had a problem with them. Maybe too much water? They like semi drought conditions and lots of sun. Some of them are fall blooming but I would think it would at least have buds on it by now.