Anglers should still keep an eye on the river gage and watch for sudden spikes. Fishing is best when the level is steady, dropping, or changing slowly. If the flow gets above 6,500 cfs (Madras gage), there are not a lot of places to find trout. Adult salmonflies should be throughout the river at this time, but if May was cool the hatch will have started late and the fish can still be looking down more than up. Golden stoneflies will probably be in the Maupin area in early June, but if the hatch started early they may already be done. These two big bugs get most of the attention this month. See Fishing the Salmonfly Hatch for advice on fishing this hatch.
The closer to you get to Warm Springs, the fewer golden stones you'll see. The closer you get to the mouth, the fewer salmonflies you'll see. Trout usually prefer the goldens to the salmonflies when both are available.
I've tried a number of salmonfly patterns, and in my opinion it's hard to beat a Clarks Stonefly. The Clarks Stonefly works well on the soft bankwater, lands gently on the water, casts more accurately than other stonefly patterns, and--due to its light weight--lets you use a finer tippet. It's also a really easy fly to tie. For some other good patterns, see Graduate School Stoneflies.
When casting salmonfly patterns, remember that most of the action is near the bank. Drift your fly through quiet water that is near overhanging vegetation; or water that is two-four feet deep and flowing over boulders; or pocket water just behind boulders; or current seams where fast water meets slow; or drop-offs below riffles; or riffly water near deeper water.
In the hatch's late stages, you'll probably do best with low-riding patterns. Take a look at the Titanic Stone for a sunken-adult pattern. This can be very effective at the end of the salmonfly/golden stonefly cycle.
Salmonflies and golden stones are not the only game in town, though. Some of the best caddis fishing I ever had on this river was in the middle of the salmonfly season; trout ignored my salmonfly imitations, but climbed all over a size 16 Soft Hackle.
The spotted caddis (aka Hydropsyche or net spinner) are hatching this month. See Net Spinning Caddis for details on this insect. Carry Sparkle Pupas in size 12-14 (olive body, tan shroud), size 12-14 Soft Hackles with an olive body, size 14 Elk Hair Caddis or X Caddis with an brown body, and size 14 Diving Caddis with a dark body and wing. By mid-month, you can expect caddis pupa imitations to work in the morning. Try patterns such as a size 16 Sparkle Pupa. Other good morning patterns for mid-month are size 18 Pheasant Tails and green drake nymphs such as the Poxyback Green Drake.
Look, too, for hatches of pale morning duns (PMDs). These occur at midday. A size 18 Parachute PMD or Sparkle Dun does well for the PMDs.
Yellow quills (Epeorus mayflies) are sometimes confused with PMDs. The Epeorus are bigger and have a yellow wing. The duns are seldom targeted by trout. Instead, use a size 12-14 yellow-bodied Soft Hackle presented with a surface swing.
Pale evening duns are another midday, mid-month event. They occur near riffles. Try a size 12-16 Light Cahill for the pale evening duns.
Yellow sallies are a June event here, too. Size 14-16 patterns are needed for the yellow sallies; see Beyond the Big Stones. Most of the action is in the evening.
From mid-month on, a size 14 Soft Hackle can be very productive in the evenings.
No matter which hatch you're fishing, most of the action will be near the bank or in the backeddies. An exception is evening midge activity, which can be offer excellent fishing. Use a size 18-20 black midge pupa near dusk. When you see trout quietly feeding near the surface in backeddies and quiet runs at dusk, they're usually taking midges.
If you've read all of the above, you've no doubt concluded that you need a big fly box for June; there's a lot happening on the Deschutes this month. The successful anglers are the ones who keep moving and keep changing flies to match shifting conditions.
With summer weather, the White River could become a problem: very hot days will cause glacial melt that will ship tons of silt down the White River. Alternatively, heavy rains on the east slope of Mt. Hood will raise the White and silt will be borne downriver. In either case, the Deschutes--from its confluence with the White all the way to the Columbia--can become too murky for good fishing. It can take three or four days for the river to clear up after one of these "events." The best advice is to check with a local source.
For more on June tactics and flies, see the Rivers in General forecast