I don't know about a cheep seed, but I have heard dandelions make great forage for deer.  Maybe you could pick a bunch that are ready to be scattered and then blow them around on the trails.  They seem like they would be really hardy.  They grow in my yard no matter what I do.

Not sure if it is applicable in your area,...but check out "field" or red clover,...it should be available at a local farmers co-op.

Hey BC,

Welcome to the site.  Red Clover you say?  Is that different the common clover?  Do the deer like it?

I put in some plots with a buddy at the end of June and we just got some pictures back. 

Turnips Food Plot:

I am pretty excited about this.  I guess the deer eat the tops in the fall and as the weather gets colder they will start to dig up the turnip root.  We have sandy soil and I wasn't sure how they would do but they are looking good.  That's my buddies daughter in the plot.  I have a trail cam up on this plot now so it will be intresting to see what we can see over the next month.  If I get any good photos I'll post them.

Tecomate Buck Forage Oats:

They seem to be coming up great.  I don't know about the oat choice and if the deer will like it but a 50lb bag was really cheap so we gave it a try.  This food plot was brand new this year and the other plots have been in for a year or two and have been limed and fertlized more.  This one we just threw down fertilizer.

Antler King Forage Mix In This Plot:

This plot has some Antler King mixed forage seed in it.  It appears to have some rafe chickoree and some other grasses.  It claims to have something for every season in it.

Food Plot ATV Trail

We found this seed at the local feed mill.  Apparently it is a blend of grasses developed for deer and turkey that is designed to be planted on logging roads and trails.  It appears to grow best in the shade.  It is pretty spotty where it gets a lot of sun.  It was developed by the WI DNR according to the guy at the feed mill.  It seems to be comming up nicley.  We disced up a old atv trail hand spread some fertilizer and then just laid down the seed by had.

You can see some of the before pictures in the food plots section of the site.  Check back next month for some trail camera photos from the turnip food plot.

Hate to say this but..... No cheap seeds in food plotting, Done right, it's a great way to kill a monster buck, done wrong..... just "wimpy" grass

Update-DEER LIKE TURNIPS-

I wanted to give you a update on my food plots.  Two weeks ago my plot looked great.  (See the first picture below) in two weeks the deer stripped the tops down to the stem.  It dosen't apper that they have been digging up the roots yeat but I hear that they don't hit them much untill we get more frost.  I was just shocked by how fast they cleaned me out.  Wouldn't you know it my deer cam was in the garage getting the battries charged.

I am hoping to hunt the property in 2 weeks.  There should be some fat turnip fed deer running around.

Looks like your hard work may pay off.  Good luck!