Rocky Prairie
Rocky Prairie Natural Area Preserve
Balsamorhiza deltoidea at Rocky Prairie
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Location	Thurston County, Washington
Nearest town	Tenino, Washington
Coordinates	46°55′12.20″N122°51′40.29″W / 46.9200556°N 122.8611917°W /46.9200556; -122.8611917
Area	810 acres (330 ha)
Designation	Nature reserve
Owner	Washington Natural Areas Program Washington State Department of Natural Resources
Website	Rocky Prairie Natural Area Preserve

Rocky Prairie is aPuget prairie that is about 56 miles (90 km) southwest ofSeattle, Washington, and about 10 miles (16 km) south of Washington's capital city ofOlympia. It sits very close to theMillersylvania State Park, the community ofMaytown, and the city ofTenino.

Old Highway 99 runs through Rocky Prairie. The part of the prairie west of the highway is called West Rocky Prairie. Both the west and east sides of the prairie have various plant and animal species. Many of the plant species are flowering plants. Both sides also have areas ofMima mounds (not to be confused with the Mima mounds atMima Mounds Natural Area Preserve about 10.5 kilometers or 6.5 miles to the west).

Rocky Prairie and the other local prairies were formed around 17,000BP (before present) during theVashon Glaciation. The Vashon Glaciation was the time period in which theCordilleran Ice Sheet extended south of the present-dayUS–Canadian border intoWestern Washington. The Vashon Glaciation was part of the Fraser Glaciation (the ice that had pushed through theFraser River basin inBritish Columbia). This occurred during theWisconsin Glaciation, the time period when ice sheets covered much of Canada and the northern United States. TheWisconsin Glaciation occurred during thelast glacial period, a time when the Earth was more glaciated. This was the most recent glaciation of thePleistocene Ice Age (the current ice age). The Pleistocene Ice Age is part of an even longer ice age called theLate Cenozoic Ice Age, which began 33.9 million BP with the formation of theAntarctic Ice Cap and continues to present day.

During the Vashon Glaciation, the Cordilleran Ice Sheet covered parts ofAlaska and Canada. The portion that extended south of the Canadian border is called the Puget Lobe. Rocky Prairie was almost at the edge of where the glacier stopped, and was only under ice for a short period of time.

Pollen data collected fromBattleground Lake (a lake about 123 kilometers (76 miles)to the southeast of Rocky Prairie) show that from 20,000 - 16,000 BP, annual temperatures in the area were about 6 ± 1 °C (10.8 ± 1.8 °F) colder than in present times (present times as of 1990).^[1] Annual precipitation was around 1 meter (39 in) less,^[1] meaning that precipitation was only about 24.5% of what it is in present times (present times as of 1990). At the glacier's edge, the wall of ice was around 200 meters (660 feet) high.^[2]

As the glaciers melted, they left behind sand and gravel. The sand and gravel drains water making the soils dry, particularly in the summer. Many of the plants that grew on these prairies were used as food or medicine by theearly inhabitants. With the eventual encroachment of forest, the early inhabitants had to burn the prairies in order to maintain them. The practice went on for millennia, and is still continued today by conservation organizations. In current times,burning is also a way of controlling invasive non-native species.

With the arrival of European settlers in the mid-1800s, new immigrants introduced plant species from where they came from so they could feel more at home. Many of these plants reproduced quickly, took over, and began replacing native species. A very problematic species on prairie lands in Thurston County isCytisus scoparius (Scotch broom). Non-native grasses have also been a problem. Most of the grass on the prairies is non-native.

Thurston County has seen explosive growth since the 1970s, and the trend is expected to continue for the foreseeable future. Between 1970 and 2010, the population density of Thurston County grew from just 41.1 persons/km² (106.5 persons/mi²) to 134.9 persons/km² (349.4 persons/mi²). The average rate of growth during those years was 2.3 person/km² (6.1 persons/mi²) per year, which is 4.3 times the global average on land.

The explosive growth is causing prairie and other natural lands to quickly shrink.

ThePort of Tacoma owns a property on West Rocky Prairie that borders on the West Rocky Prairie Unit (the state owned property). The size of the property is 746.56 acres (302.12 hectares).^[3]

On July 17, 2006, the Port of Olympia and the Port of Tacoma made an agreement to build a railway logistics center.^[4] The next day, the Port of Tacoma purchased the property at Rocky Prairie from Citifor, Inc. for a price of overUS$21 million (about $70,000 per hectare or $28,000 per acre).^[4] Later that year, local groups got together to block the proposal.^[4]

In 2008, there were several meetings with the public in which the Thurston County commissioners and representatives from the ports were present. Many citizens had the opportunity to speak in front of the public and voice their opinion about the proposal. Almost everyone that spoke was opposed to the proposal. On June 30, 2008, the Port of Tacoma and the Port of Olympia dropped the proposal to put in the logistics center.^[4]

The Port of Tacoma decided to sell the property.^[4] In April 2010, a developer from southern California made a down payment on the property.^[4] They formed a company called Maytown Sand and Gravel, LLC.^[4] After about a year, the property went back to the Port of Tacoma.^[4] The company had defaulted on their loan.^[4]

In 2019, the Port of Tacoma is selling the property to NorthPoint Development, LLC, a development company centered inRiverside,Missouri for a price of $24 million (about $79,000 per hectare or $32,000 per acre).^[5] The company is trying to get Thurston County to change the zoning of the property to industrial.^[6]

The current proposal is to have a logistics center on West Rocky Prairie. There would be six million square feet of warehouses (which is about 56 hectares or 138 acres).^[6] There would be a massive increase in truck and freight train traffic,^[7] and numerous negative secondary environmental impacts.

Rocky Prairie is divided into several different properties. The two land owners west of Old Highway 99 are theWashington State Department of Fish and Wildlife and the Port of Tacoma. A major land owner east of Old Highway 99 is theWashington State Department of Natural Resources. There is also another property on the east side owned byThurston County which has a gravel pit located on it. Some of the prairie on the east side is private property, and has pastures and houses on it.

In West Rocky Prairie, the property that belongs to the Washington State Department of Fish and Wildlife is called theWest Rocky Prairie Wildlife Area. The size of the property is 810 acres (330 hectares).^[8][9] Part of the property is wooded, and part of it is in the prairie. The West Rocky Prairie Unit has over 300 acres (120 hectares) of woods, 360 acres (150 hectares) of wetlands, 40 acres (16 hectares) ofQuercus garryana (Garry oak trees), and 300 acres (120 hectares) of Mima mounds.^[10]

The closest weather station to Rocky Prairie with a long period of record collection is at theOlympia Regional Airport in the city ofTumwater. Under theKöppen climate classification system, the climate of the Olympia area is classified asCsb.^[11] The C means that it is a temperate climate, meaning that the winters are chilly to mild. The s means that it is a Mediterranean climate, meaning that the summers are dry. The b means that the summers are warm but not hot. This type of climate is also called awarm-summer Mediterranean climate. In this type of climate, the winters are rainy. The area south of Olympia is inhardiness zone 8A.

Rocky Prairie plant species (Click "show" to display table)
Division	Class	Order	Family	Genus and species	Common name(s)
Pinophyta	Pinopsida	Pinales	Pinaceae	Pseudotsugamenziesii var.menziesii English translation: False hemlock spruce -Archibald Menzies - variety[12]	Coast Douglas-fir Pacific Douglas-fir
		Apiales	Apiaceae	Lomatiumtriternatum[13] English translation: Small border - three leaves[12]	Nineleaf biscuitroot
		Apiales	Apiaceae	Lomatiumutriculatum[13] English translation: Small border - inflated[12]	Common lomatium Spring gold
		Asparagales	Asparagaceae	Camassiaquamash[13] English translation: Sweet - sweet[12]	Camas Common camas Common camash Small camas Quamash
		Asparagales	Iridaceae	Sisyrinchiumangustifolium[13] English translation: Pig snout - narrow leaf[12]	Narrow-leaf blue-eyed-grass
		Asterales	Asteraceae	Achilleamillefolium[13] English translation: Achilles - thousand leaves[12]	Common yarrow Yarrow
		Asterales	Asteraceae	Antennariamicrophylla[13] English translation: Antenna - small leaf[12]	Dwarf everlasting Littleleaf pussytoes Pink pussytoes Rosy pussytoes Small pussytoes
		Asterales	Asteraceae	Balsamorhizadeltoidea[13] English translation: Balsam root - triangle shaped[12]	Deltoid balsamroot
		Asterales	Asteraceae	Solidagocanadensis[13] English translation: Heal (to make well) - Canadian[12]	Canada goldenrod Canadian goldenrod
		Asterales	Asteraceae	Solidagospathulata[13] English translation: Heal (to make well) - small spathe[12]	Coast goldenrod Dune goldenrod
		Asterales	Campanulaceae	Campanularotundifolia[13] English translation: Little bell - round leaf[12]	Harebell
		Asterales	Campanulaceae	Howelliaaquatilis[14]	Water howellia
		Asterales	Asteraceae	Erigeronspeciosus[13] English translation: Early old man - spectacular[12]	Aspen fleabane Garden fleabane Showy fleabane
		Asterales	Asteraceae	Eriophyllumlanatum[13] English translation: Woolly leaf - woolly[12]	Common woolly sunflower Oregon sunshine
		Asterales	Asteraceae	Microserislaciniata[13] English translation: Small lettuce like plant - narrow lobes[12]	Cutleaf silverpuffs Cut leaf microseris
		Asterales	Asteraceae	Sericocarpusrigidus[13]	Columbian whitetop aster
		Asterales	Asteraceae	Hieraciumalbertinum[13]	Houndstongue hawkweed Western hawkweed
		Caryophyllales	Caryophyllaceae	Cerastiumarvense[13] English translation: Horn - farmland[12]	Field chickweed
		Dipsacales	Caprifoliaceae	Symphoricarposalbus[13] English translation: Fruit clusters - white[12]	Common snowberry
		Ericales	Ericaceae	Arctostaphylosuva-ursi[13] English translation: Bear,bunch of grapes - bear's grape[12]	Kinnikinnick Pinemat manzanita
		Ericales	Primulaceae	Dodecatheonhendersonii[13] English translation: Twelve gods -Louis Forniquet Henderson[12]	Broad-leaved shooting star Henderson's shooting star Mosquito bills Sailor caps
		Fabales	Fabaceae	Lupinusalbicaulis[13] English translation: Wolf - white stems[12]	Sicklekeel lupine
		Fabales	Fabaceae	Lupinuslepidus[13] English translation: Wolf - elegant[12]	Dwarf lupine Pacific lupine Prairie lupine
		Fagales	Fagaceae	Quercusgarryana[10] English translation: Oak - Nicholas Garry[12]	Garry oak Oregon oak Oregon white oak
		Lamiales	Lamiaceae	Prunellavulgaris[13] English translation: Quinsey - common[12]	Blue curls Brownwort Carpenter's herb Common self-heal Heal-all Heart-of-the-earth Woundwort
		Lamiales	Orobanchaceae	Castillejalevisecta[13]	Golden Indian paintbrush Golden paintbrush
		Liliales	Melanthiaceae	Toxicoscordionvenenosum[13] English translation: Toxic garlic - venomous[12]	Death camas Meadow death camas
		Liliales	Liliaceae	Fritillariaaffinis[13] English translation: Dice box - similar[12]	Checker lily Chocolate lily
		Malpighiales	Violaceae	Violaadunca[13] English translation: Violet - hooked[12]	Early blue violet Hookedspur violet Sand violet Western dog violet
		Poales	Juncaceae	Luzulacampestris[13] English translation: Lucciola - plains[12]	Field wood-rush Good Friday grass Sweep's brush
		Poales	Poaceae	Festucaidahoensis[13] English translation: Straw - Idaho[12]	Blue hunchgrass Idaho fescue
		Poales	Poaceae	Danthoniacalifornica[13] English translation: Étienne Danthoine - California[12]	California oatgrass
		Ranunculales	Ranunculaceae	Aquilegiaformosa[13] English translation: Eagles' claw - beautiful[12]	Crimson columbine Red columbine Western columbine
		Ranunculales	Ranunculaceae	Delphinium nuttallii[13] English translation: Dolphin -Thomas Nuttall[12]	Nuttall's larkspur
		Ranunculales	Ranunculaceae	Ranunculusoccidentalis[13] English translation: Little frog - western[12]	Western buttercup
		Rosales	Rosaceae	Malusfusca[15] English translation: Apple - dusky[12]	Oregon crabapple Pacific crabapple
		Rosales	Rosaceae	Potentillagracilis[13] English translation: Potent, small - graceful[12]	Graceful cinquefoil Slender cinquefoil
		Rosales	Rosaceae	Rosapisocarpa[13] English translation: Rose - pea-like fruit[12]	Cluster rose Swamp rose
Photographs shown were not necessarily taken at Rocky Prairie, and most likely were not taken there. Photographs of similar types of plants may be substituted if that species/subspecies photo is not available.

Rocky Prairie animal species (Click "show" to display table)
Phylum	Class	Order	Family	Genus and species	Common name(s)
Arthropoda	Insecta	Hymenoptera	Apidae	Bombuscalifornicus[16]	California bumble bee
Arthropoda	Insecta	Lepidoptera	Hesperiidae	Euphyespropertius[14]	Propertius duskywing
Arthropoda	Insecta	Lepidoptera	Hesperiidae	Euphyesvestris[14]	Dun sedge skipper Dun skipper Sedge witch
Arthropoda	Insecta	Lepidoptera	Hesperiidae	Hesperiacomma[14]	Common branded skipper Holarctic grass skipper
Arthropoda	Insecta	Lepidoptera	Hesperiidae	Hesperiajuba[14]	Jagged-border skipper Juba skipper Yuba skipper
Arthropoda	Insecta	Lepidoptera	Hesperiidae	Ochlodessylvanoides ssp.orecoastus[14]	Coastal woodland skipper
Arthropoda	Insecta	Lepidoptera	Hesperiidae	Politesmardon[14]	Mardon skipper
Arthropoda	Insecta	Lepidoptera	Hesperiidae	Politessonora[14]	Sonoran skipper Western long dash
Arthropoda	Insecta	Lepidoptera	Lycaenidae	Icariciaicarioides ssp.blackmorei[14]	Puget blue
Arthropoda	Insecta	Lepidoptera	Nymphalidae	Euphydryaseditha ssp.taylori[14]	Taylor's checkerspot Whulge checkerspot
Arthropoda	Insecta	Lepidoptera	Nymphalidae	Speyeriazerene ssp.bremnerii[14]	Valley silverspot
Chordata	Amphibia	Anura	Ranidae	Ranapretiosa[6]	Oregon spotted frog
Chordata	Aves	Anseriformes	Anatidae	Brantacanadensis	Canada goose
Chordata	Aves	Accipitriformes	Accipitridae	Haliaeetusleucocephalus[14]	Bald eagle
Chordata	Aves	Passeriformes	Turdidae	Turdusmigratorius	American robin
Chordata	Mammalia	Artiodactyla	Cervidae	Odocoileushemionus ssp.columbianus	Columbian black-tailed deer
Chordata	Mammalia	Rodentia	Geomyidae	Thomomysmazama ssp.tumuli[17]	Tenino pocket gopher
Chordata	Mammalia	Rodentia	Sciuridae	Tamiasciurusdouglasii	Douglas squirrel
Photographs shown in animal species chart were not necessarily taken at Rocky Prairie, and most likely were not taken there. Photographs of similar types of animals may be substituted if that species/subspecies photo is not available.

• List of geographic features in Thurston County, Washington
• Scatter Creek Wildlife Area

• Geography of Thurston County, Washington
• Grasslands of the United States

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