Lovely! Kind of a Heinz 57 lawn right now.

Here's what I would do. I would raise the mower up to the highest setting and mow whatever grass gets that tall.

You have some weeds which grow outward from a central point. Dig those out as you can get to them.

If you don't have a sprinkler, then use an oscillator type. They work well on rectangular lawns. Put out some empty cat food or tuna cans and time how long it takes to fill the cans. That is your target time for weekly watering. This time of year in your area you only need to water once every 3 weeks. By July you will be up to weekly watering. This will kill off many weeds and prevent many new ones.

That soil looks awful. I would begin fertilizing with alfalfa pellets (rabbit chow) at 10 pounds per 1,000 square feet. Then in a month repeat at 20 pounds per 1,000. You can continue that as often as you like up to monthly for the rest of the season. Get the alfalfa pellets at your local feed store in 50-pound bags.

If you find the soil will not absorb all that water at one time, then you might want to soften the soil. It takes awhile to explain how to do that so either you can search this forum for shampoo and hard soil or you can wait and ask after you've determined you get runoff with an oscillator type sprinkler. The rain bird type of sprinklers are awful on rectangular yards. Oscillators are simply excellent.

Then in August you can work on any issues you still have with the lawn. Chances are you will want to reseed or overseed. August is the time to do that. Not now. If you do it now you will have a crabgrass lawn by July. You might anyway but if you water the way I suggested, you should not have much if any crabgrass.

You have kentucky bluegrass and tall fescue in yoir lawn. I would cut the tree down, grind the stump down, screened topsoil to fill in the hole, and then resod the damaged area. You will have much more success with sod than seed this time of year. The area doesn't look very big so it shouldn't be that expensive. Plus in the long run sod will save you a lot of time. After your sod puts down some roots you can apply your preemergent herbicide and start spraying any weeds that you have. If you must seed you will need to look into Tenacity herbicide.

Thanks for all the advice. The yard is covered with dandelions right now. Can I put down weed killer and alfalfa pellets at the same time? We are about to get three days or thunderstorms starting tomorrow night if the weather is correct so not sure if I should wait.

OMFG. I would NEVER recommend to remove a tree with no reason given! It's a TINY tree. There is nothing in the picture that says this is a dire situation requiring removal of a TREE.

I have to wonder, is Joneboy just a troll?

Regardless, DON'T do what she/he recommended.

BTW, why look into Tenacity for dandelions? Wow... speechless.

So are you saying the tree is salvageable? I know nothing about trees but the trunk on that thing looks so dead. It is flowering but the whole thing just looks so decrepit.

From the original post "Obviously there is a dead tree that needs to be removed as well." The jason777 said the tree is dead is there a reson to keep it? Maybe I was't clear on why jason777 should use Tenacity, maybe gsweater didn't read the original post, or maybe he/she doesn't understand Tencity's use as a preemergent herbicide that you can seed cool season grass into. I didn't even address the OP's question about dandelions, you can use 2,4D. By the way gsweater what is it that you recommend jason777 should do? So gsweater I'll lay it out for you in simple chapter and verse since you clearly don't understand the issues with seeding in the what would now be considered late spring,and I'll try to keep it short and use small words so you can keep up. To seed you need to have good seed to soil contact,so you will need to aerify and/or rake up all the dead stuff. Once you've disturbed the soil, seed and then roll. Use Tenacity right after you seed and then again 3 weeks later, watered in with .15 inches of water. Three weeks after the last application of Tenacity apply the low rate of prodiamine or pendamethlin, be careful not to apply to much because your probably going to need to reseed a few spots in the fall. Now after you seed you have to keep the seed wet for around 10 days if your using tall fescue if your using kentucky bluegrass it's more like 21 days, this means watering for a couple minutes every hour or two between the hours of 8 a.m. And 5 p.m. Once the seed has germinated you can back off the water to twice or three times a day until the tall fescue has tillered out a couple of times, or the kentucky bluegrass is starting to put out rhizomes. Also, as soon as the seed germinates you need to feed it some nitrogen something quick release, like ammonium sulfate or urea, so you can get it moving to out compete any weeds. A .5 of a pound of nitrogen per thousand square feet every couple of weeks until the area is filled in. Okay now the area is mostly covered and it's now the end of May or the beginning of June just in time for summer heat and disease pressure. Also, now that the plants are hopefully mature enough you can start spraying any weeds that the Tenacity missed.Take a picture now because by the end of August that area is not going to look like it did in May. The plants that you seeded back in the end of April beginning of May did not have enough time to develop a deep root system and store enough carbohydrates to fight off the heat, drought, and disease pressure that is coming. Now,if you sod you cut out the area,rake, lay the sod,roll if you need to. Give the sod a good soaking once in the early morn. with a hose. The sod should be rooted down in about a week. Once the sod has rooted down apply pendamethlin or prodiamine and water in with .5 inch of rainfall or irrigation. Then one shot of fert at .5 to a 1 pound of nitrogen per thousand square feet. Or the best option wait until early fall and resod then and you don't have to worry about preemergent herbicides and the sod has all fall,winter,and spring to develop a strong healthy root system.

I did say the tree was dead but that was an amateur's perspective. Here is a close up of the trunk. Do you think it is salvageable?

So I understand the concept of mowing very high so the grass prevents weeds, etc. but what should I do with the areas that don't have any grass at all and just weeds?

"I didn't even address the OP's question about dandelions, you can use 2,4D." Enough said.

Again, cannot disagree more with jonesboy. I'm convinced she's a troll.

No need to "lay it out" for me, I have a Bachelor's in Agronomy from OSU with a Masters in Applied Sciences working for one of the largest growers in the US. Thanks for your amateur advice though! It was cute. End result is if you follow the advice he gave, especially the latter advice (given that we are so close to summer), you'll have to expect a toasted lawn by mid-June and a complete redo in fall. Your call because it's your back and your wallet. Good luck!

2,4D's claim to fame is it's effectiveness on dandelion.,not the most ideal time to spray in the spring fall would be better but you will get some control. You must of fell asleep that day in weed science. No comment on the tree? Go back and read my post again I was explaining to you why spring seeding is a waste of time and money. Sodding now would be a better option and sodding in the fall would be the best option. As far as the troll thing goes I have actually take the time to give jason777 some real advice and you started with the inflammatory language "OMFG. I would NEVER recommend to remove a tree with no reason given! It's a TINY tree. There is nothing in the picture that says this is a dire situation requiring removal of a TREE.
I have to wonder, is Joneboy just a troll?
Regardless, DON'T do what she/he recommended.
BTW, why look into Tenacity for dandelions? Wow... speechless." without any advice whatsoever.

As much as I've had my fill of controversy on lawn forums, here I go again.

gsweater, your opinion about that particular tree definitely differs from the OP and from joneboy. Still, it is an opinion. Why get yourself and everyone else worked up about it? It is much easier to state your opinion without the drama and move on. Besides it launched a discussion better suited to the tree forum than the lawn forum. And I thought joneboy's advice about tree removal was very good (for a lawn forum). Why would you call someone a troll for replying to a specific statement in the OP's original question? I just don't get that.

If the tree is flowering, it is not dead...but it sure is ugly. I'd remove it simply because it's offensive looking. If you want to replace it with a nicer tree, dig a new hole to the side.

Back to the OP, you can apply weed killer with alfalfa pellets. You can apply anything with alfalfa pellets.