Jumis (pronounced you-miss) was an important god of the harvest for pre-Christian Latvians living on their landschaft villages. He controlled fertility and prosperity and was one of very few Latvian male earth gods. His favor was greatly desired by farmers. At the end of the harvest, during the festival of Mikeli, a special ritual is performed called the catching of Jumis, apparently intended to capture his spirit for the fields of the village.
The word Jumis itself is apparently related to a Sanskrit word, jama that means twin, although the word Jumis is often translated to mean "spirit of the fields." The two meanings were sometimes combined and the word thus applied to two individual fruits or vegetables that have grown into one mass or to a single stalk of a plant that bears two ears of wheat or barley instead of the more common single variety. These unusual plants were used in the catching of Jumis ritual. One of these was left uncut after the harvest. Its ears were tied in a knot and bent back down to the ground, where they were weighed down with a stone or buried until the villagers were satisfied that the soil had been sufficiently reimpregnated by the essence of Jumis, as represented by the special plant. They also usually knocked the grain out of the plant and scattered it into the soil before taking the plant and braiding it into a wreath, which would then be presented to a local matriarchal figure. She would hold onto it until the following spring, when its seeds would be sown into the fields or the whole wreath placed under a rock in the fields. A special, extra-large loaf of bread was usually baked at about this time, as well, and its consumption was seen as quite an honor for the recipient.
In art, Jumis is depicted as a short man wearing clothes that resemble, and are possibly made from, staple crops such as barley, hops, and wheat. He is sometimes accompanied by his wife, who has similar fashion sense.
This is the symbol of Jumis:
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Except usually it's probably not in crappy ASCII form. It (the symbol) was especially popular during the iron age, and most often appeared in elaborated form (much like medieval monks' intensive decorations of particular letters in religious texts) on textiles from the period, although it can apparently still be found on the silos and barns of modern Latvian farmers. According to a Latvian clothing manufacturer's site, it is supposed to represent two interlocking stems of the harvest, thereby symbolizing "fertility and the mystery of life," which would fit in nicely with the rest of the Jumis motif.
Sources: http://www.webwm.com/raksti/putns.htm
http://pagan.drak.net/wwcrew/deities/jumis.html
www.nordwear.com.lv/jumis.htm
http://www.latinst.lv/holidays.htm