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Agricultural Preservation

Our county is looking into ways to preserve agricultural areas in a county that is feeling some increasing pressure to develop. Does anyone have any ideas or examples of counites that have established 20, 10, or 5 acre tracts as agricultural preservation districts?


Bedminster Township, Bucks County, PA has been very successful with this. Almost the entire township is zoned AP-Agricultural Preservation.

Section 408 AP Agriculture Preservation District

(1) Use Regulations

a. Uses permitted by right include:

Al General Farming

A2 Nursery

A3 Intensive Agricultural

A6 Noncommercial Kennel

A8 Agricultural Retail

A9 Forestry

BI Detached Dwelling

B6 Group Home

B11 Air Park

C1-C9 Residential Accessory structures and uses

D1 Place of Worship

D3 Library or Museum

D7 Municipal Building

El Recreational Facility

E3 Golf Course

E6 Recreational Camping Park

H2 Emergency Services

J3 Temporary Structure

J8 Accessory nonresidential radio and television towers, masts, aerials, flagpoles and dish

b. Uses by Special Exception include:

A7 Equestrian

D2 School

D4 Hospital

D5 Nursing Home

D6 Cemetery

D9 Day Care Center

E2 Private Camp, Park, Recreational Area

E4 Community Center

E5 Private Club

G17 Cottage Development or Private Camp

G20 Guest House

Hl Utilities

H5 Radio or Television Transmitter

19 Storage Yard

J6 Wind Energy Conversion System

c. Uses by Conditional Use include:

J4 Temporary Community Event

J7 Air Landing Field

(2) Area and Dimensional Requirements

Unless a greater area or dimensional regulation is stated in Section 405, Use Regulations, for a
specific use, all permitted uses shall comply with the following requirements:

a. . Sites containing less than ten (10) acres. A lot, parcel or tract of land that has a lot
area of less than ten (10) acres as of the effective date of the Ordinance which created the
AP District shall comply with the following standards:

Minimum lot size = 80,000 sf
Minimum lot width = 200 ft
Front yard = 85'
Side = 30, 75' aggregate
Rear = 100 ft
Height = 35'
Max Bldg Cov = 7%
Max Impervious = 10%

b. Sites containing ten (10) acres or more. A lot, parcel or tract of land that has a lot area
of ten (10) or more acres as of the effective date of the Ordinance which created the AP
District shall comply with the following standards:

(i) All proposals for subdivisions and land developments shall complete a site analysis as
specified by Article VI of this Ordinance.

(ii) No more than forty percent (40%) of prime farmland or farmland of statewide
importance (Capability Classes I, II and III) may be developed.

(iii) All proposed lots and development must be located on the portion of the tract which is
situated outside the Non-Buildable Site Area.

(iv) Lot Size - Each lot permitted on the buildable portion of a tract of land shall contain a
contiguous area of at least one (1) acre (43,560 square feet). No portion of this one (1)
acre minimum lot area may contain any of the following natural resources:



Floodplain Soils


Lake or Pond

The lot shall be enlarged accordingly to meet the unrestricted one (1) acre lot size.

Up to twenty percent (20%) of the one acre lot may contain areas of wetland margins or
lake and pond shorelines. Woodlands, steep slopes, farmland and agricultural soils that are
not part of the NonBuildable Site Area may be included within the required one (1) acre
lot area.

(v)Building Envelope

a. All residential lots shall have a contiguous building envelope of at least ten thousand
(10,000) square feet. The purpose of the identification of the building envelope is to
provide sufficient area and flexibility for the general location of a building, driveway,
parking, patios and other improvements and site alterations while meeting the natural
resource protection standards and minimum setback requirements.

b. The building envelope may include woodlands, steep slopes and agricultural soils areas
that are not part of the Non

Buildable Site Area. The building envelope may not contain any of the following resources:
floodplains or floodplain soils wetlands, lakes, ponds or watercourses wetland margins or
lake and pond shorelines

The preservation of agricultural soils in this ordinance is what really puts a limit on development in the area, as the entire township is pretty much agricultural soil.
I don't think you can honestly consider it an AG preservation zone if development is allowed to occur at a one acre per dwelling unit rate. Large lot minimum (40 acres), a limit on permitted uses, and restricting uses that have a negative impact on commercial agriculture will be a good start in preserving AG lands. Also, initiate strict criteria for ammending the comp plan to remove property from an Agricultural Resource designation..


In PA courts have found that restricting lots to minimum of 3(?) acres is the most you can go without being overly restrictive. 40 acre minimum lot size would never fly, it would probably be laughed out of the public meeting in which it was proposed.

If I own a 40 acre parcel I have a right to develop it since SFD are a use by right. You're basically telling me that I have to either farm it or build one house and be happy.

That would never hold up in any court, at least not around here.
You bring up a very valid point. We're talking about two very different areas, with much different types of AG uses I suspect. In central Washington, relatively large tracts of land are needed to grow tree fruit or grapes. Anything less than 40 acres is not normally considered appropriate for agriculture of that type. Having said that, in most agricultural communities, minimizing the amount of residential development in AG zones is an acknowledged tool in AG preservation. Residential untis are considered an impediment to AG operations due to their inherent incompatability. Unless they are controlled, AG is normally pushed out of an area.
Here in Yakima County, we have a 40 acre minimum in our agricultural resource area, with one small lot exemption to allow for a 1 to 3 acre parcel every 15 years. Another consideration when comparing the two areas is the fact that Washington is a Growth Management State. One of the mandated goals within our growth management statutes is the preservation of agricultural resource areas. Rules are fairly strict regarding its protection.

Linden Smith

The best practices for using zoning to preserve agricultural areas is to set the minimum lot size for AG areas at whatever the reasonable minimum is to constuctively farm in that region. For most areas that would be greater than 20 acres. It should include one princpal residence and one accessory residence for a farm worker. Selling off lots should be done with a zone change.

Setting the minimum at 1-5 acres is politically expedient, but can contribute to an unreasonable consumption rate in the Ag to residential transition. There is no case law which states that large lot ag standards are a "taking" and if the elected officials can exercise some backbone, large lot zoning is the best tool for keeping real estate speculation out of rural areas.

In Kentucky, this means that, yes, if a farmer wants to give his son or daughter an acre for a homesite they have to get a zone change to do so. Just having this process in place puts actual development in front of the Planning Commission, and gives the public the oppourtunity to speak out on the issue frequently.

It also helps to have a limit on extension of urban services, such as sewer lines, water lines, road development, etc., but that is a whole 'nother level of complexity that most rural areas cannot support.


In PA, municipalities have been taken to court over large lot zoning and lost. In the midwest and other areas large lot ag zoning is still a real feasibility, but in areas that need the restrictive zoning the most it isn't feasible. So we limit the amount of ag soils you can develop, and also require a resource free acre to put a house on. So in essence you take a 100 acre parcel, you are preserving at minimum 60 acres (the whole area is comprised of prime ag soil). Seems like a good idea to me, especially in an area where agricultural is a dying economy and we are preserving it simply for the fact that politicians can say they are fighting sprawl and preserving our rural character. But in reality our rural character started to be lost in the 50s when Levittown was built.

Keep in mind we are not talking 5,000 acre farms around here and in FL. We see a 500 acre farm as being enormous.
Here in Yakima County, accessory farm dwellings are not allowed on a parcel unless it is at least 20 acres in size. We've had a problem with accessory farm dwellings turning into additional single family residences when the parcel stopsa being farmed.

The 1-3 acre small lot exemption to allow for a small lot once every 15 years was a political cave-in when we updated our comp plan to comply with the Growth Management Act. With the apple industry currently in the tank, we are once again fighting pressure to alloow for more development within the AG areas. The jury is still out. We'll know the final outcome sometime this fall.

Linden Smith

Michael, I've seen lots of different types of political "outs" used to make rural zoning more palatable to the landowners, some constitutional, some not. The time exemption seems to stand, but I've seen an "in family conveyance exemption" that is clearly not, but it never gets challenged. The accessory dwelling is never permitted unless the minimum lot size is met. Conveying an accessory dwelling would require a zone change.

Mike, I wonder if those cases failed due to something in your state laws that override the local ordinances, or if those were appeals of zone change requests that fell to a weak local judge. Using agric soils as a regulatory tool is a good idea, it helps to tie the regulations to things that make up the basis of the areas character.

I sometimes tell zoning administrators that it helps to think of zoning as the bell around the cats neck. When there is going to be a change in land use, even for just an acre, the bell rings and you have a public hearing. Sure its breaucratic, but I've seen places where more than half of the development going on in an area never gets to the planning commission due to all the loopholes written into zoning just to placate the RUGGED individualist. Those compromises make the regulatory scheme seem silly and useless, and that is what gives zoning a bad name.

Most ag zoning needs to be updated though to allow for a wider array of activities now that farm subsidies are driving small farmers out of business. Selling items produced on the site, value added products, and fostering farmers markets work well to keep ag production a viable economic enterprise.
Under our Growth Management Act, there is a very limited criteria that would allow land to be taken out of AG Resource designation. These include parcelization and pressures to develop due to proximty to an already urbanized area. Basically, the determination must be soil based with the above exceptions. We are currently using a combination quantitative/qualitative analysis with the help of GIS to determine the combined value for AG taking all allowable variables into account. Once that is done, the Planning Commission gets their turn at it. Public pressure has attempted to include an economic aspect to the analysis, but we keep reminding the PC that State statute won't allow it.
I think you confused my post with the other from PA. Our AG Resource area IS based on soil classifications according to their suitability for AG uses associated with this area however.
Part of our struggle stems from the fact that there is a large volume of AG land in very close proximity to our cities. This is running right up against pressures to develop. There are more issues than I can discuss here, but we are basically in the process of making recommendations to redesignate some of the closer in areas in the hope that we can extract better protection for the areas further out.

Lee Nellis

Minimum lot sizes are not usually -- unless they are very large -- a reasonable way of protecting agricultural land. Even in areas of small farms, like northern New Mexico, it works better to assign development right, then require that they be transferred either to nonproductive lands or to a small portion of the productive lands. You need to use other tools, too, depending on what is available where you are: local right to farm requirements that are stricter than your state RTF law, differential tax assessment (its possible to use this effectively in only a few states), ag districts, access management, etc. It is also advisable to work with a local land trust to help farm families find ways to permanently protect land, and if you can pull it off, to set up a purchase of development rights program. American Farmland Trust has a lot of helpful information: check out their web site.

PS: Pennsylvania seriously needs a new Supreme Court …