New Mexican, 17 December 1892
He may have created similar decorations in other years. He had experience planting and growing evergreens.
Gardeners Monthly, vol. 29, November 1887, page 326. Available from Google Books.
The laurel that he used was probably Texas mountain laurel. It is listed in the book Native Plants for Southern Landscapes by Judy Mielke (University of Texas Press, 1993). Texas mountain laurel grows in Texas, New Mexico, and Mexico. It blooms in March and April, so its purple flowers would not have been present when Mathias made the wreaths and evergreen strings. I think the plant's white beans would look beautiful on Christmas wreaths.
Sophora secundiflora beans at the Desert Demonstration Garden in Las Vegas, Nevada, October 2003. Photo by Stan Shebs [GFDL (http://www.gnu.org/copyleft/fdl.html), CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or CC BY-SA 2.5 (http://creativecommons.org/licenses/by-sa/2.5)]. Available from Wikimedia Commons.
One of the churches that he probably decorated was the Cathedral Basilica of St. Francis of Assisi. The parish was founded in 1714, and the construction of the cathedral was completed in 1887.
Cathedral Basilica of St. Francis of Assisi. 4 June 2009. Photo by John Fowler [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)]. Available from Flickr and Wikimedia Commons.
He may also have decorated San Miguel Chapel, which was built between 1610 and 1626.
San Miguel Chapel. 15 October 2009. Photo by Shiny Things [CC BY 2.0 (http://creativecommons.org/licenses/by/2.0)]. Available from Flickr and Wikimedia Commons.
Perhaps he also decorated Nuestra Señora de Luz Church, which is 13 miles southeast of Santa Fe. The church was built in 1880.
Front of the Nuestra Señora de Luz Church, Canoncito, New Mexico. Library of Congress, Prints and Photograph Division HABS: NM,25-CANCI,1-1. Image courtesy of the federal HABS—Historic American Buildings Survey of New Mexico project (rotated and retouched). Available from Wikimedia Commons.
I do not have photos of Mathias' Christmas decorations, but this image of evergreen decorations in Santa Fe, New Mexico may help to paint a mental picture of his creations.
IAIA Museum of Contemporary Native Arts, Santa Fe, New Mexico. Photo by Bill Johnson [CC BY-SA 4.0-3.0-2.5-2.0-1.0 (http://creativecommons.org/licenses/by-sa/4.0-3.0-2.5-2.0-1.0)]. Available from Wikimedia Commons.