The Best Way to Preserve Old Documents, Plants, and Keepsakes

Written by Joely Rogers

Picture frames, mat boards, and glazing help protect artwork and keepsakes from deterioration, but how do you protect unframed materials? Especially those with organic materials like dried roses from a wedding bouquet, or something more extensive, like a collection of plants.

My grandfather was a horticulturist, which is a person who uses scientific knowledge to cultivate and propagate plants. I recently inherited one of his herbaria from the early 1970’s. Herbariums are collections of dried plant specimens usually mounted and systematically arranged for use in scientific studies.

Plants present storage challenges similar to art prints and canvases since plant materials are composed of cellulose, the basic component of most papers, textiles, and wooden objects. My grandfather had kept his herbarium in a dimly lit, air-conditioned room, so it was at least protected from light and temperature fluctuations. I was concerned though with the visible acid migration from the plants onto the paper containing his hand-written notes.

Objects containing plant materials in combination with other organic and inorganic substances create more problems than those made from a single material because changes in one substance can cause physical and chemical alterations in an adjacent one. In the picture below you can see the difference between paper with an attached plant specimen (left) and one without (right).

All of plants in the herbarium are common and easy to find; however, my deceased grandfather’s handwriting cannot be replaced. Since my main concern was preserving his handwriting, I decided to remove all the plant specimens to prevent any further acid migration from them to the paper. I didn’t want to throw them away, but wasn’t sure how to store them in an archival manner. The National Park Service’s “Conserve O Gram” on Preparing and Storing Herbarium Specimens suggests mounting dried plants on acid free, pH neutral 100% alpha cellulose or cotton rag paper using adhesive linen tape and then placing them in an acid free, pH neutral fragment envelope. My company sells a variety of archival products for image mounting and display. I selected our Bainbridge Artcare™ acid free mount board, see-thru archival mounting strips, and protective Clear Bags™ for mounting and storing the dried plants.

Wearing cotton gloves to keep the oils from my hands off the plants, I carefully removed all of the plant specimens and mounted them onto the foam board using the mounting strips. Since the specimens were all fairly small, so I chose 5”x 7” backer boards. We can cut custom mount boards, however, in any size up to 40”x 60”. The mounting strips are peel and stick and you can cut them into different sizes. None of the adhesive touches the plants, only the polyester strip. I placed acid free labels with the specimen’s name on the back on each foam board and then placed them in individual Clear Bags. These bags are museum quality, acid-free and lignin-free crystal clear. The adhesive strip is actually on the bag - not the flap - so that your contents won’t get stuck to the adhesive when being inserted or removed.

Finally, I placed his herbarium and all of the plant specimens in one of our Museum Storage Boxes. These boxes are made of acid-free buffered board which helps neutralize airborne pollutants and other contaminants. I am storing the box in a temperature-controlled room. Hopefully, by taking these steps, it will last another 40 years or longer