How high is too high when it comes to dividend stocks? Of course, every income investor wants as much yield as possible. However, they also want the lowest risk possible.

The good news is that some stocks with especially juicy dividends aren't overly risky. The bad news is that others are quite risky. Here are two ultra-high-yield dividend stocks I'd buy right now -- and one I wouldn't touch with a 10-foot pole.

Backed by Uncle Sam

Easterly Government Properties (DEA) is a real estate investment trust (REIT) that primarily leases properties to federal agencies that it views as mission-critical. These agencies include the Federal Bureau of Investigation, General Services Administration, and Veterans Administration.

The company noted in its recent investor presentation that 97% of Easterly's lease income is "backed by [the] full faith and credit of the U.S. government." That doesn't mean that the REIT doesn't have any risks; it does.

For example, Easterly's high dividend yield of nearly 7.6% could be in jeopardy. The company's 2023 guidance for funds from operations (FFO) doesn't leave much wiggle room to cover the dividend at current levels at the low end of the guidance range.

I'm not too concerned about a dividend cut, though, because I expect Easterly to deliver results well above the low end of its guidance. Also, with the possibility of a U.S. recession increasing, I think that the Federal Reserve's interest rate hikes could soon grind to a halt. When interest rates begin to fall again (which they will, sooner or later), it should provide a nice catalyst for Easterly's share price.

Close to dividend royalty

Enterprise Products Partners (EPD 0.48%) isn't far away from becoming dividend royalty. The midstream energy company has increased its distribution for 24 consecutive years. Randy Fowler, Enterprise's co-CEO and CFO, said in the first-quarter conference call that the company has "good cash flow growth that'll support distribution growth down the road."

That distribution doesn't have to grow at all to be attractive. Enterprise's distribution yield currently tops 7.6%. The stock is also performing well so far this year.

Business is booming for Enterprise. The company reported record pipeline and fee-based natural gas processing volumes in the first quarter. Its natural gas liquids marine terminal volumes also reached all-time highs. Total marine terminal volumes came close to setting a new record as well. 

What about the company's long-term prospects? Co-CEO Jim Teague said in the Q1 call, "It's very hard to make a bearish call for oil in the medium to long term. And it's hard for us to be too constructive on natural gas." I suspect that Teague is right. If he is, Enterprise should continue paying and increasing its distributions for a long time to come.

Too many problems

While I'd gladly buy shares of Easterly Government Properties and Enterprise Products Partners right now, it's a different story with Office Properties Income Trust (OPI 3.54%). Sure, the REIT's dividend yield of nearly 16.4% might seem enticing. But Office Properties simply has too many problems.

For one thing, the company lost money in the first quarter of 2023 based on generally accepted accounting principles (GAAP). Its normalized funds from operations (FFO) sank by almost 16% year over year. Nearly one out of 10 of its office properties are currently unoccupied. 

Office Properties acknowledged in its Q1 update that it faces significant headwinds, including "volatile macroeconomic conditions" and a difficult financing environment with high interest rates. My concern is that the REIT's issues aren't just temporary. With more people working from home as a result of the COVID-19 pandemic, I'm not sure that the office real estate market will ever be what it once was.

Office Properties plans to merge with Diversified Healthcare Trust to diversify its portfolio. I think this is a good move overall since Diversified Healthcare owns medical office buildings and life sciences properties that are more attractive than general office properties. However, the healthcare REIT has some problems of its own.

Perhaps Office Properties' fortunes will improve down the road. For now, though, I'd stay away from this ultra-high-yield dividend stock.