Mesquite Harvesting & Processing

Excerpted from The Tumbleweed Gourmet by Carolyn J. Niethammer
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Because mesquite pods have the shape and size of a green bean they are often called mesquite “beans,” which has caused some misunderstanding of how the fruit is used.

Not all of the mesquite pod is edible — a great deal of it is indigestible fiber. The most accessible edible portion of the pod is the pulp or pith between the brittle outside and the hard seeds. Ordinary bean pods do not have this pith. This portion has a very sweet, brown-sugary flavor and can be ground into a meal for use in baking . The pith surrounds a number of stone-hard seeds, inside of which are found the protein-rich embryos or true seeds.

It is almost impossible to crack the hard seed coats with home methods; however, in the past, Indians who lived in the desolate Pinacate Mountains on the Mexican-American border devised a stone implement, given the name “gyratory crusher” by its discoverer, archaeologist Julian Haydn. It looks like a grinding stone with a hole through it and for years investigators thought the artifacts they found were just worn-out grinding stones, or metates. But Hayden surmised the hole had a purpose. As it turns out, when a heavy wooden pestle is manipulated in these stones, the mesquite seeds can be cracked, an ingenious bit of technology invented by protein-hungry people.

A modern-day equivalent of the gyratory crusher is a fairly common piece of farm and milling equipment called a hammermill. A hammermill can crush and grind both the pith and the seeds of mesquite pods and sift out most of the debris automatically. People who can beg or talk their way into the use of one of these machines can provide themselves with great quantities of high-protein mesquite meal with little effort.

Desert Harvesters owns a community hammermill and holds annual community millings. Click here to see our hammermill page.

Mesquite Pod Harvesting and Storage Tips

When to harvest
Mesquite pods ripen for harvesting throughout the summer. The season in Tucson typically begins in late June and stretches into late September. Though the harvest can extend into October in cooler areas such as Sahuarita, Sonoita, or Patagonia. Native trees are adapted to our two rainy seasons (winter and summer), and typically go through two flowering phases, one in the spring (April/May) and the other after the monsoon (August). This results in two fruiting phases. Ripe pods may range in color from yellowish tan to reddish (not green), and are dry and brittle. They come off the tree with little pulling.

Where to harvest
Harvesting pods in the city is safe and convenient if you can find an area that hasn’t been cleared of all its vegetation or contaminated by pollutants (see “Where not to harvest” below). We have harvested quality pods from washes, small drainages, city parks, backyards, and along low-traffic neighborhood streets. Often, it is the trees in the city that are the most abundant producers because they are receiving supplemental water or runoff from adjoining hardscape (rooftops, patios, and streets).

Where NOT to harvest
Do not harvest from areas that are polluted or contaminated. These include:
- Highway corridors and other areas with high volumes of vehicular traffic and air-borne pollutants
- Areas where there is known or suspected use of pesticides or herbicides (you don’t want your pods to come into contact with soil that is sprayed with Round Up)
- Avoid trees with roots that are in the direct vicinity of telephone poles because they are treated with toxic wood preservants
- Avoid trees that are receiving high volumes of polluted runoff. Sources of such pollution can include oil and brake fluid accumulating on streets or pesticides from non-organic farms and yards.
- Avoid gathering pods from the ground where there is likely to be animal waste such as dog and cat droppings.

If you are unsure about harvesting in a certain area, just err on the side of caution and avoid it. Start observing mesquite trees in the landscape more closely and you will figure it out in no time!

How to harvest
Ripe pods are best picked from the tree rather than gathered off the ground, since they will be cleaner and there is far less chance that there will be any mold on the pods. Ripe pods only require the slightest pull to remove them from the tree. If you need to pull hard the pods are not ripe.

Pods can be picked up from the ground after they have fallen as long as they have not been contaminated (see “Where not to harvest above”), have not started to decompose and mold, and as long as they are rinsed off and thoroughly dried in the sun for 2-3 days.
Avoid pods with black mold spots on them.

Taste before you pick
Once you have found a tree that you want to pick from go ahead and TASTE one of the pods (watch out for the very hard seeds). If it tastes good to you, go ahead and pick from that tree. The flavor can vary widely from one tree to the next. If you are unfamiliar with the taste of good mesquite, it is a good idea to sample pods from several different trees.

Note: Preferred flavors vary depending on who is doing the tasting, though Desert Harvester Anastasia has found that non-native Chilean mesquite pods often have a chalky taste to them that is reminiscent of Pepto-Bismol. Native velvet, screwbean, and honey mesquites tend to have a more fruity flavor and are seldom chalky.

Be prepared
We usually carry a few bags with us wherever we go during mesquite season so that we can pick if we happen to find a good tree. Don’t forget about the wildlife; leave some pods for them too.

Cleaning mesquite pods
Rinse your pods, if desired, by dunking them in a pail of water, swishing them around and then drying them in the sun (or in your oven at low heat) for several days until they are dry enough to snap in two when bent.

Storing mesquite pods
Store in a dry, rodent-free place until milling day. We often store the dry pods in clean garbage cans, buckets, or paper or cloth bags. Be sure your pods are completely dry before you store them to prevent molding. You can dry pods by laying them out on a cloth, metal roofing, or the hood of your car in the sun for 2 to 3 days. You know they are dry when you can easily snap them in two when you try to bend a pod.

Bruchid beetles will likely hatch out of the pods during storage (they make the small holes in the pods), but this is not something to be alarmed by since they are harmless. If you let the bruchid beetles escape, they will leave on their own accord. This is a good reason to store the pods in a shed rather than your bedroom as Desert Harvester Brad did. He came home from a trip to find little bruchid beetles flying all about. A shock at first, but the window was opened, the beetles released, and the pods were then put in the shed out of reach from any rodents (who like to eat the pods).

For those that are set on reducing the potential of bruchid beetles hatching out during storage you can try the following:
-Store the pods in paper bags, and put the bags out in the sun at intervals during the summer. This reportedly decreases the incidence of the bruchid beetles.
-Freeze your pods. But be sure to take them out of the freezer at least 3 days prior to a milling event and set them out in the sun so they will be thoroughly thawed and dry before milling. We’ve had to refuse to grind the pods from people who took their pods out of the freezer the day of, or the day just before a milling because they were to moist to grind.
-Put pods in a solar oven for a few hours, then take them out and make sure they are thoroughly dry. Once thoroughly dry, put the pods in a sealed container.

Please be sure the pods you bring for milling are clean and free of gravel, dirt, or any other debris that could damage the mill or contaminate the flour. Only clean pods will be ground.

Estimated time, volume, and value of a neighborhood mesquite pod harvest
One person can leisurely pick 5 gallons of whole pods from a neighborhood pruned up velvet neighborhood street tree (not picking pods on the ground) in about 1 hour and 20 minutes.

If it takes another 15 minutes drying/storing/cleaning the pods (little cleaning is needed if only clean pods are harvested)

It takes about 5 to 10 minutes to grind that 5 gallons of whole pods.

To be conservative, let’s say it takes 2 hours total to pick, clean, dry, store, and grind 5 gallons of whole pods into 1 gallon of flour.

If that 1 gallon (5 pounds) of mesquite flour were sold at the bargain price of $10 per pound ($14-20 per pound is more common price), it would earn $50, thus netting the neighborhood harvester/seller a $25 per hour wage. This assumes the flour is sold directly to the customer, most likely at a mesquite milling event in the neighborhood, and that the harvester harvested the pods in his/her neighborhood to eliminate transportation time and costs.

Note that harvest time could likely be significantly reduced if time efficiency were more the goal, and the pace were not leisurely; could pick from trees that have not been pruned up, and thus need a ladder for picking; if pods were knocked down onto a sheet on the ground.

Mesquite flour weight/volume ratios
10 lbs of whole velvet mesquite pods (about 6 gallons) were ground into 7.5 lbs (or 600 ounces) of flour

5 lbs of whole pods (about 2.5-3 gallons) were ground into 3.25 lbs (or 260 ounces) of flour

1 cup of velvet mesquite flour weighs about 5 ounces

16 cups in a gallon, so one gallon of velvet mesquite flour weighs 80 ounces or 5 pounds

Additional mesquite pod/flour weight/volume ratios
On average 5 gallons of whole dry velvet mesquite pods weighs about 7 lbs, though this can range from 5 to 9 lbs due to how tightly the bucket is packed/filled with pods.

On average a pound of whole pods grinds down to 0.6 to 0.75 pounds of mesquite flour, or 60 – 75% of the pod weight (but again this can vary depending on the pods).