Man, those modern railroaders have it good. If they're curious what kinds of freight cars are in trains, they go to the tracks and take photos. If they're curious about how locomotives travel around, they visit one of the tracking sites to see where UP 5623 is. They've got Street View, aerial photos, etc.
That doesn't work as well for those of us modeling the past. If we want to set a scene, we have to search dusty archives, examine the background of old photos, and dig a lot deeper for not very much information.
Some photos (such as this photo of Del Monte's Plant 51 can hint at the question. We see lots of single sheathed boxcars, and the front two boxcars are both Texas and New Orleans (a SP subsidiary), but there's so many questions left unanswered - how fast did the cars turn over? What are those cars in the back? Where are the cars going?
Luckily, there are some other sources. Tom Campbell, who models R Street in Sacramento, was doing research on what his area looked like in the 1950's, and along the way found out about a fight whether the SP had to switch cars from the Western Pacific going to a local grocery distributor.
The California Railroad Commission case over this issue included, as evidence, a list of all the freight cars that arrived at Valley Wholesale Grocery's spur from January 1935 to June 1936. Tom and I made a spreadsheet of the cars so we could sort them by railroad, origin, delivery date, or even what kind of car it was. Check out the spreadsheet and background document.
Here's some of the surprising facts I learned from the data. What do you see? Post here, or on Tom's blog entry about Valley Wholesale Grocery.
* There were 170 cars delivered to Valley Wholesale Grocery over about a year and a half. That's a new car arriving every three days for a short spur sandwiched between two other industries. That's a reasonable rate, even for a model railroad. The majority of the cars (140/170) were SP, T&NO, and PFE, with many of the cars coming from elsewhere in Northern and Central California.
* 57 of the 170 cars are, I suspect, evaporated milk and other milk products from milk plants in Ripon, Modesto, Gustine, and Galt. I didn't know that evaporated milk was so popular in the 1930's, or that it was often used as a base for infant formula.
*31 of the 170 cars are from South Vallejo, and arrive weekly. My first guess is this is flour and other products; there had been a General Mills mill there; it burned in August 1934. Time to check out some period Sanborn maps for ideas.
* Twelve cars came from Battle Creek, Michigan, and at least one was from General Foods (aka Postum), bringing probably Post cereal, Jell-O, Maxwell House coffee, and Postum. Some of these were 50' auto boxcars with larger doors intended for carrying partially disassembled wagons and automobiles. The long cars were probably good for the light and bulky packaged foods. I've got a few 50 foot boxcars on my layout, but I only use them on team tracks. I suspect they'd also be useful at some of the dried fruit packing plants, carrying Sunsweet prunes off to an eager public!
* Two of the cars came from Palacios, Texas, on the Texas coast. Palacios was a big shrimp port, so it seems like Sacramento must have liked their canned shrimp!
* All the cars from Gustine, the location of the large Carnation Milk Products cannery, were refrigerator cars. Most of the other delivered cars were boxcars. What did Valley Wholesale get in refrigerator cars? It doesn't look like they had any kind of refrigeration in the warehouse, though there was an ice cream maker in the next building in the 1950's.
* What's that Norfolk and Western coal hopper doing in Sacramento, just arrived from Peoria? Was it a typo by the railroads or California Railroad Commission, or did they heat the building with coal at the time?
So what does all this tell me about freight cars for the Vasona Branch?
* More Southern Pacific freight cars. Valley Wholesale Grocery may not be representative of my canneries, but it suggests a lot of SP cars stayed on the SP.
* More T&NO cars. There was one T&NO car arriving for every Southern Pacific car.
* More single-sheathed, outside-braced boxcars. They're about half of the boxcar fleet seen.
* Use the 50 foot auto boxcars for the packing houses sparingly.
Time to build more cars!