Levels of major elements (N, P, K, Mg, Ca) in `Early Black' cranberry (Vaccinium macrocarpon Ait.) tissues changed during the season (April to October). A distinct pattern was associated with each tissue type (old leaves, woody stems, new shoots, roots, fruit) and each element. However, the pattern for a given element in a given tissue was similar from year to year. For example, nitrogen levels in old leaves rose early in the season and then declined in old leaves as new shoot tissue was produced. The early-season rise in nitrogen levels in old leaves coincided with a decline in nitrogen in woody stem tissue. Changes in the amount of applied nitrogen led to changes in nitrogen levels in new shoots after a 2 year Iag. While N, K, Ca, and Mg content (% dry weight) in roots is lower than that in other tissues, there is great biomass of root tissue, so that root tissue represents a large pool of these elements. Roots, along with woody stems and old leaves may represent a reservoir of major elements for new shoot development early in the season, prior to fertilizer application. Levels of the major elements in new shoot tissue achieved a steady state in August, an indication that this is a good time to collect tissue for routine testing.