Last fall I gathered acorns from a single oak that straddles our property line and used them as a feed supplement for my hens over the winter months. This year I made it a
formal goal to be a bit more ambitious about gleaning acorns. So far this year I've collected over 65 pounds of them, and they're still coming down in my area. I do think of them as booster fuel for hens during the coldest and harshest months of the year, so most of what I've gathered has been put up in buckets where they will, I hope, escape the notice of rodents who would love to help themselves to this caloric feast. But I've also been feeding the less prime acorns to the hens as they come in, so I thought it would be a good time to post about some points that have come up for me as I've been gathering them and using them for feed.
First off, I've become rather selective about which acorns I pick up and bring home. I gleaned a little factoid from the coverage of the recent recall of factory farmed eggs. Namely that salmonella is carried by rodents, which can introduce the disease to previously healthy poultry flocks. Squirrels are rodents, are abundant in my region, and show a famous interest in acorns. Many of the nuts I find bear evidence of nibbling by squirrels. I do not gather these acorns. Some acorns have broken shells that may or may not be due to squirrel nibbling. They may have taken the damage when they fell on a hard surface. I err on the safe side and don't risk collecting such acorns.
Another type of damage common to acorns is a shell that has split along its grain. This is clearly not caused by rodents, but it still presents a problem. Acorn nutmeats are very high in fat, and they will turn rancid fairly quickly once exposed to air. So acorns with split shells are not candidates for storage. I do bring home a number of acorns with reasonably small splits in the shell and feed them to the hens very quickly. It's a way of using up what I can, even if they can't be kept for storage.
The last type of damage that causes me to reject an acorn at collection is a small hole that indicates a weevil has penetrated the shell and is currently feasting on the nutmeat. If you see two holes (rare when the nuts have just fallen) the weevil has been and gone. Now these nuts too could be collected for the hens if I were willing to segregate the ones with such holes. Laying hens, after all, will just as happily eat weevils as they will acorns. But if the infested acorns are stored with the pristine ones, the weevils will eat their way from one acorn to the next, and there is a net caloric loss with each step up the food chain. So it's either segregate, or don't collect. Mostly I opt not to collect those acorns.

Last year I used a small burlap bag to crush the acorns. Each day I placed a couple handfuls in the bag and crushed them on a flat rock by using a 5-pound hand sledge. The problem with that setup was that the burlap didn't hold up. Fairly quickly I found that a glancing blow from the hand sledge could propel an acorn straight through the fabric. This year I've upgraded to a denim bag crafted from a tattered pair of my father's jeans. I just cut one of the legs off and sewed up the cut edge with some sturdy hand stitching. So far it looks as though the denim is going to answer nicely.
A note on oak trees -
Quercus is a big family, or more properly speaking, a genus. (Isn't
Quercus just about the best word, ever?) I'm not going to tell you than I can tell any of the 600+ oak species apart by name, because I can't. What I can say is that the size, shape, quality, and drop time of acorns varies considerably from one species of oak to another. Acorns started falling here in August, and there are still oaks dropping their bounty now in October. It pays to look around and keep looking. If you don't find acorns of good quality from one particular type of oak, you may well find them from another type a few weeks on.
Storage was a problem last year. Mice are quite happy to help themselves to any sort of seed or nut kept in our garage over the winter months. I've taken steps to prevent this this year and recommend you think about how to keep any acorns you collect away from rodents, particularly in light of the risk they might transmit salmonella to your poultry.
I did a little poking around to find out what the value of my acorn gleaning might be in terms of feed for the hens. I have no clue what they do or don't contribute in terms of nutrients. But the average laying hen needs - at an absolute maximum - 350 calories per day to maintain optimum laying rate. Presumably this is for hens who live in Siberia and lay jumbo sized eggs. Even so, let's say my hens need that many calories in winter. After all, they don't get any supplemental heat, only shelter from the wind. The other factoid I turned up is that acorns have 1700 calories per pound. Now I don't know if that figure is just for the extracted nutmeats, or what. Clearly the acorn cap and shell contribute nothing to the hens' diet. So let's say that of the 65 pounds of acorns I've gathered so far, we have to eliminate a whopping 25% of that weight to account for the unusable portion. That leaves about 49 pounds worth of acorn nutmeats, which have an astonishing 82,875 calories. Divide that by the maximum caloric needs of my four-hen flock (1400 calories per day for all four of them) and speaking very conservatively we're looking at a two-month supply of feed from gleaned acorns.

Now, as mentioned, it's not at all clear that acorns alone would give the hens what they need in terms of vitamins and minerals. But I did lay in a supply of
comfrey, dried from our own production earlier in the year, and I know that's a highly nutritious feed for poultry. Between these two "free" feeds, plus our kitchen scraps, some recycled eggshell for calcium, and whatever mystical stuff chickens find in
deep litter bedding, I would bet they're pretty well on their way to a complete laying hen diet. I plan to use the acorns only as supplemental feed in combination with the locally grown and milled organic grains they normally get. But it's clear to me that if it were absolutely necessary, we could probably get the hens through the winter with aggressive acorn gleaning (provided of course that the oak trees didn't take another
gap year as they did in 2008). If that were the case, we almost certainly wouldn't light the hens to maintain their winter laying quota, so their caloric needs would go down, which would make the acorns stretch even further. And that's without even touching on hickory nut gleaning.
Aside from musing about strategies for maintaining my mini-flock in a worst case scenario, I see this as a social justice issue. We in the industrialized countries "go to the table" ahead of citizens in the developing world. We eat first, because we can afford to. Not only can we pay more for the most basic foodstuffs, such as grains, but we choose to eat animal products which are produced at the cost of a huge amount of grain - further driving up global market prices for these commodities. And after we've eaten our fill of grain-intensive meat or dairy or eggs, we then feed our pets with meat produced in an identical fashion. Thus we consume first, and consume more than the poor. My flock and my pets are no exception to this reality. Though they are pastured on our lawn, and we supplement what feed we buy with all sorts of food that would otherwise be wasted, our hens nonetheless eat grain that could have gone to the world market and contributed to lower prices for grain. My hens compete with impoverished families and hungry children, and they win by virtue of the money I have at my disposal.
So whatever I can do to come up with free food for my hens not only saves me money and makes my homestead less dependent on a fragile distribution system, it also brings a little more balance to the relationship between rich and poor countries. That's a real motivation. Gleaning acorns is fun for a while. But when it gets a little boring, or my back starts to ache, I push on just a little longer with the acorn hunt. Because I believe that actions - even small, imperfect, insufficient actions - have consequences. Even if I never see the results, I know that gleaning this food is the right thing to do.