Yields on 10-year U.S. Treasury bonds jumped, climbing above 3.7 percent at one point on Wednesday, the highest since November.

That’s good, right? Higher yields mean bigger profits in your bonds and bond funds, don’t they?

Not so fast. The rising yields mean bond prices have fallen. In the middle of May you would have paid full face value for a 10-year Treasury bond. Today, it would be worth only about 95 percent as much. You’d have lost 5 percent in two weeks, more than the interest earned in a year.

It’s a reminder that bonds, though generally safer than stocks, are not risk-free. If you want real security, certificates of deposit and other bank savings are the best choice.

When people describe U.S. Treasury bonds as “safe havens” for worried investors, they’re focusing on the bonds’ all-but-non-existent default risk, since the government can use its taxing power to guarantee all payments to bond holders will be made as promised.

But once the bonds are sold by the government, they can be traded among investors in the secondary market, where supply and demand dictate prices. Here, they are subject to a variety of risks, such as inflation risk and interest-rate risk.

Recently, bond investors have focused on signs of economic recovery and heavy government spending to stimulate the economy, two factors that can drive inflation up. The Federal Reserve typically responds to inflation worries by pushing up interest rates. Investors who expect rates to rise in the future, start reacting now.

As a practical matter, an investor who expects 10-year Treasuries to pay 3.5 percent, 4 percent or 5 percent in the future won’t pay full price for one sold a few weeks ago. The lack of demand drives that bond’s price down.

Bonds with longer maturities, such as 10 years rather than two, are affected more, since no one wants to be stuck with a low-yielding bond for the long term.

Now the question: is a 10-year Treasury, or a mutual fund stuffed with them, an appealing investment at today’s lower price? Buy today and you can lock in a yield exceeding 3.5 percent. That’s not bad, given the average five-year CD pays just over 2.2 percent.

The problem comes if you want to get your money out of the Treasury bond before the 10 years end and the government pays back your principal. If prevailing rates go up in the meantime, your bond could sell for far less than you’d paid.

On the other hand, with an FDIC-insured CD, you have a government guarantee against any loss of principal or interest.

Long-term investors should have some portion of their holdings in bonds. That’s most easily done through mutual funds.

But trying to play the short-term ups and downs of the bond market is a game for experts. While 3.5 percent looks okay today, Treasury yields have often been much higher. If they rise further, you could take a beating on a bond investment bought this spring.

If your real goal is to find a safe place to keep cash, bank savings make a lot of sense, whether you choose ones with fixed rates or step-up options that let you profit from rising rates.

Though you’ll generally pay a penalty to get your money out of a CD early, you can use a laddering strategy to get the best mix of yield and accessibility. The CD Ladder Calculator will show you how.

Use the CD search tool to find the best deals. If you’re willing to tie your money up for five years, you can find some CDs that rival the 10-year Treasury. Discover Bank (Stock Quote: DFS) has one paying 3.64 percent, while one offered by AIG Bank (Stock Quote: AIG) pays 3.4 percent.

— For more ways to save, spend, invest and borrow, visit MainStreet.com.