The Nature Conservancy has suspended a range of practices, including the sale of ecologically sensitive land to its trustees as home sites, in the wake of press accounts describing the Arlington-based nonprofit's activities and concerns expressed by some of its 1 million members.

The Conservancy, the world's richest environmental group, said it has halted all "conservation buyer" real estate transactions until the charity's board of governors reviews the practice in June. A Washington Post series last week reported that many buyers have been current and former Conservancy state trustees.

The Senate Finance Committee's chairman and ranking Democrat announced last week that they plan to look into the sales, which are designed to limit intrusive development but generally allow buyers to construct houses.

Under the program, the charity buys raw land, attaches some development restrictions and then resells the properties to supporters at greatly reduced prices. Buyers give the Conservancy cash payments for roughly the amount of the discount, a sum that is then written off the buyers' federal income taxes.

Other articles described how the Conservancy's board and leadership council today include executives and directors from corporations that have paid millions in environmental fines. The series also showed how the 52-year-old charity's alliances with Fortune 500 companies had helped it amass assets totaling more than $3 billion.

In a statement posted on the Conservancy Web site, nature.org, the organization said it also has:

• Suspended all new logging and other "resource extraction activities" on its nature preserves. The Post articles detailed how in Texas City, Tex., the organization had drilled for oil and natural gas under the last native breeding ground of a highly endangered species of grouse known as the Attwater's prairie chicken. The suspension will not stop natural gas production on the Texas preserve, a spokesman said.

• Suspended all new "cause-related marketing partnerships." The articles told how the Conservancy had sold its name and logo for use on consumer goods, including toilet cleaner and other products made by corporations whose executives and directors had sat on the Conservancy's governing board and advisory council.

• Suspended all new loans to employees. The articles disclosed that the Conservancy had extended a $1.55 million loan to its president, Steven J. McCormick, and then misidentified the interest rate. After being questioned by reporters, McCormick repaid the loan.

The Conservancy statement criticized The Post series, titled "Big Green," for containing what it described as "mischaracterizations" and a "lack of context." Even so, the organization plans a detailed review of the programs discussed.

"We take the broad issues the articles raised very seriously," the statement said. "The Conservancy's Board of Governors will dedicate its entire June meeting to a frank and open discussion of our practices, policies, and procedures. The board will focus on the Post's specific charges. . . .

"We will be paying particularly close attention to issues relating to how we engage and work with our Board and state chapter trustees. We are committed to making permanent and substantive changes where needed."

The meeting will be closed to Conservancy members, but will include time for "some sort of public discussion," a spokesman said.

Over the past week, the Conservancy's board has paid for three full-page advertisements in The Post, each stressing the organization's accomplishments and its dedication to preserving undeveloped land.

Sen. Charles E. Grassley (R-Iowa), chairman of the Finance Committee, and ranking Democrat Max Baucus of Montana are drafting a letter to the Conservancy seeking answers to a range of concerns about the land deals and other governance issues.

"Taxpayers have the right to know how the Nature Conservancy conducts its business," Grassley said in a statement on Friday. "I'll be overseeing the charity's actions, asking tough questions and following through until satisfactory answers are given."