The mulberry most often associated with silkworms is Morus alba, white mulberry. Here is a list of white mulberry trees which were growing in Seattle (at the time of the book's publication) from Trees of Seattle (by Arthur Lee Jacobson, 2006):

1) University of Washington, a male west of old Drama/TV Building
2) 15th Ave and E. Olive, NW corner
3) 23rd Ave E. and E. Prospect St., E side
4) Kubota Garden Park, E side near Camperdown elms
5) LDS Church at 8th Ave NE and NE 57th St.
6) 2544 NE 143rd St.
7) 43rd Ave. NE and NE 80th St., NE corner yard
8) 4405 SW Holgate St. street tree
9) 3821 E. Galer St. -- 4 street trees

Keep in mind that you should ask permission from University and Parks Department grounds crew and private homeowners before harvesting leaves from any of the trees.

Sericulum offers information on how to raise silkworms. Here is their page on using mulberry leaves as food.

Season All Season
Date 2006-03-16
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The Seattle Department of Transportation, in cooperation with the City Arborist’s Office, has created lists of recommended trees for planting in Seattle. While the DOT is more concerned with street trees (trees planted in the strip of ground between the sidewalk and the street), their recommendations may help you. In addition, since the DOT deals with buckled sidewalks on a regular basis, these lists may account for a problem like yours.

Here is the web address:
http://www.seattle.gov/transportation/treeplanting.htm#recommend

The City Arborist’s Office also has a page of trees that they recommend *with reservations*. (White birch and weeping white birch are on the list.) At the bottom of this list are Prohibited Trees.

Here is that web address:
http://www.seattle.gov/transportation/treeswithreservations.htm

Season All Season
Date 2008-01-17
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