With King Snakes, there are a couple of different substrates that can be used:

Aspen Shavings:Aspen shavings may be used for King Snakes. The shavings cannot be cleaned and so have to be removed and replaced with fresh shavings when dirty.  If you use aspen shavings the urine and feces can be scooped out with a cat litter scoop, and replaced with fresh aspen as needed. Be sure to remove soiled substrate as soon as possible; urine-soaked material will become a breeding ground for bacteria, which could harm your King Snake. If you use this type of substrate you will have to place your snake in a secure area to feed it; you do not want it to ingest any of the shavings.

At least once a month, all shavings should be removed and disposed of, and the entire enclosure cleaned and disinfected before new shavings are placed inside. This is particularly important if your King Snake has musked inside the vivarium, as the musk is a diluted form of excrement, which should be removed as soon as possible.

Do not use Cedar or Redwood Shavings these are toxic for all animals and should never be used in predator or prey enclosures. Cedar and redwood should not be used in constructing housing for any animal, nor in any furniture or paneling in a vivarium in which any animals are housed.

Newspaper: Layers of newspaper have been used for years in animal keeping. It is relatively absorbent when several layers are used, and inexpensive to replace. However, the inks used in printing are known to be harmful to animals. Unprinted sheets may be obtained at shops selling moving supplies, or roll ends may be obtained from some newspaper companies. As with printed newspaper, it is relatively absorbent when several sheets are used, especially when layered with paper towels. Unlike printed newspaper, the unprinted sheets and rolls are not impregnated with potentially harmful inks that could harm your King Snake.

Easily obtained and relatively inexpensive, paper towels make an excellent substrate for reptiles with belly injuries and those in the early stages of quarantine.

Beech Chippings: Beech Chippings are readily available from most Reptile shops and are quite an attractive substrate to have in the vivarium. It comes in three different grades - small, medium or large, so you can choose the size which is most suitable for your snake. It allows for spot cleaning, although it is not as absorbent as Aspen. It is not a good substrate for burrowing snakes.

Coco/Orchid Bark: Some reptile shops may recommend the use of Coco or Orchid bark for King Snakes, but this substrate is more appropriate for snakes that require higher humidity levels. It is unadvisable to use this substrate for King Snakes as they are susceptible to respiratory infections (R.Is) if the humidity becomes too high.

Astroturf® / Artificial Grass :

Astroturf® was the first artificial grass floor covering. Since then, carpet manufacturers have come out with many grades of artificial grass. Hardware shops usually have two or more grades. The least expensive is generally the best to use. It is more flexible, a key factor for thorough cleaning and disinfecting. Pieces can be washed and disinfected repeatedly before they require replacing. Astroturf® is cheap enough that several pieces can be cut for each enclosure and rotated each cleaning day. The pieces of artificial grass substrate sold in small, prepackaged pieces in many pet shops and mail order pet suppliers are the same as the product sold in builder supply shops.