I have a map with a Site feature class with two key attributes: species and year. I have successfully displayed sites using Symbology > Multiple Attributes > Quantity by Category. I used species for the first of the three value fields. I used year for the Symbol Size. This gives me a different color for each species, and a different size for each year.
Unfortunately, on the legend, I get a separate symbol for each combination of species and year. With about 10 species and 5 years, this means I get 50 symbols on the legend. All I want is one symbol showing the color for each species, and one scale that shows year by size.
I think this has got to be a common issue. Any suggestions on how to clean up my 50-item legend?
You could also consider creating "shadow" Feature Classes in the TOC (Table of Contents) of ArcMap with the appropriate legend (symbols). Then create a legend based on these while excluding all the other layers you want to display and make the legend non-dynamic to retain the shadow layers, then deselect the shadow layers in the TOC to make them invisible.
Thanks for your suggestion -- worked exactly as you described. And it's a good enough solution, although it doesn't give me quite what I want, because, in the original legend, I get, for example, the species indicator ("CBL"), with a yellow circle with the year ("2009") next to it. After ungrouping, I'd ideally like to have just "CBL" plus the yellow circle, but I don't see a way that I can edit the "2009" out of the legend.
before you do what I have suggested, right click your legend and choose properties. Go to the items tab. On the left side, right-click the feature you would like to change the style of and click style. Maybe one of the styles doesn't have the date attached?