During migration the parula warbler does not frequent haunts typical of its breeding ground; in fact such are not to be found in much of the country over which it travels; nor does it especially frequent the coniferous woods to which it is partial in summer. It is to be found almost anywhere, in many kinds of trees, though it seems to show a decided preference for deciduous woods. There, it may often be seen drifting through the highest tree-tops in mixed groups of migrating wood warblers, gleaning insects amidst the freshly opening foliage. Referring to the Buckeye Lake region in Ohio, Milton B. Trautman (1940) writes: "The transient Parula Warblers usually displayed a preference for large pin oak and shingle oak trees and a marked preference for one shingle oak in particular. This oak was in the Lakeside Woods, and more Parula Warblers were observed in it than in all of the remaining trees of the woodland. A transient often displays a marked preference for certain types of trees, but it appears unusual for a single tree among many of the same kind to retain yearly so marked an attraction for a particular bird species." The migrating parula warbler is often seen in roadside trees and in shade trees in parks and gardens. It even visits our orchards, where one of the most charming sights of springtime is to see this gay-colored, tiny warbler flitting about in search of insects among the apple blossoms, a delightful bit of color contrast in a beautiful setting. _Nesting._--The nests of the northern parula warbler that we used to find in southern Massachusetts were all located in haunts similar to those described, and mostly in old orchards heavily festooned with beard moss (_Usnea_). We could usually find three to five nests in a well-populated orchard, but they were so well hidden in the hanging moss that we may have overlooked some. A casual observer would never notice one, but with practice we learned to recognize a rounded, cuplike, thick place in a bunch of _Usnea_ as indicating a nest. The nests were usually made in bunches of moss that hung from horizontal or sloping branches and were from 5 to 15 feet above the ground, more being below than above 12 feet. Some nests were in red cedars, or savins (_Juniperus virginiana_), scattered among other trees or growing in open stands by themselves; they were located in bunches of _Usnea_ close to the center of the tree and often within reach from the ground. Occasionally, isolated trees on the edges of swamps or on the shores of ponds were sufficiently covered with the lichen to contain nests, and these were sometimes as much as 20 feet above the ground. The nearest approach to a colony that I ever found was in a small cedar swamp, not over an acre in extent, that jutted out from the shore of a lake into rather deep water.